I inherited a non-running Seamaster 30, need advice

Hello everyone! A few years back, my grandfather gave me his old watch. He said it wasn't working anymore but that it might be worth getting it looked at. I personally haven't worn a wristwatch since childhood and have never really been into them, but i think this particular looks rather neat.
Anyway, it sort of got a little forgotten about until now. When i looked through some stuff i came across it again today, and decided to get to know the watch and watches in general a little better, as well as a crash course in some terminology. I might be off on some terms, forgive my possible mistakes.

Visually, the watch is rather rough i`d say. My grandfather was a hard working mechanic and the watch shows that. There are some deeper dings and scratches around the case. The caseback is quite dented and gouged from some violent tool use. The hippogriff is barely visible. Also, on the crown and on one of the strap lugs are some tiny lumps which i can only imagine are welding spatter,. Needless to say, the crystal has seen better days. The minutes hand is slightly bent and missing most of the lume.

But from what i can tell, the linen dial is in good, original condition apart from some stuff around the edges which i think might just be some looseish dirt particles. The lugs are a little rounded which, together with the faded hippogriff, might indicate that it has been polished, but possibly it might come from heavy wear. Would like some feedback on this. It`s also got an omega sign on the crown.

I had read about polywatch and later that toothpaste might work to polish up the crystal. I reckoned this one was too far gone for me to to any further harm so i tried the toothpaste trick in order to get a better look at the dial. I gotta say, it worked surprisingly well! Well enough to turn from very matte (to the point where it was hard to see detail in the dial) to clear enough that i would personally not mind using it like it is. However, it might make sense to change it out along with any other work i might have someone do to it.
Is there a good way to tell whether or not the crystal is original?

I gave the crown a turn, and it felt rather stiff so i decided not to fiddle with it any more. After seeing the damage to the hand and caseback i was worried about the carnage i would eventually find inside, but i had no good tool to open it and didnt want to damage anything more than what is already there. But i half heartedly tried to push and twist with my thumb, and to my surprise, it actually worked! Safe to say, the complete lack of an o ring helped me there. Finally i could have a peek inside and immediately i see a hair wiggled around one of the wheels and i think yey! maybe an easy fix i can do myself! so i take a closer peek in order to see how to best free it, and well. Turns out its not a hair after all. Its the rather fittingly named hair spring. Its mangled and i can see a loose end sticking out. Unsure if it has sheared off somewhere or if it came off from where the end is secured. And its quite hard to see whats going on without any good magnifier.
Any thoughts about how bad this might be? Why would this spring get mangled? Could it indicate other problems deeper inside and does it make sense to have it repaired given the condition of the watch?

Other than that, I didn`t do anything more inside. Other than the hair spring, i couldn`t see any issues and to me it seemed neat and tidy with few scratches, unmarred screws and no corrosion that i could notice.

So I assume the best step now is to take it to a watchmaker. However, i assume they are not all the same. And my economy is very tight. So any advice on this would be greatly appreciated!

Actually just any and all input would be great! I would like to know as much as i can about this watch. I still haven`t decided if i should keep it or sell it. I like the watch a lot, but i also don`t like the feeling of wearing a watch, and while handy to have a timekeeper on my wrist, it really doesn`t bother me to look at my phone. But i will of course try it out if i get it running. Maybe something has change since the last time i used one.

Wow I just now realized how much i wrote. I hope some of you manage to battle through it, because i don`t want to redo it now. Thanks in advance for any help!

The pictures also aren`t the greatest perhaps. I`m happy to take more if needed. I also hid the serial no because i read somewhere that this was good practice, but maybe it is not needed.

Very nice dial. A lot of sentimental value in the case scars. As a family piece, it would be a keeper for me, no question.

Post where you are located, and someone will suggest a watchmaker for you.

Hello and thank you both for the replies!

About the hairspring and balance wheel, ouch. Thats not what i was hoping to hear. My service and repair budget is currently very tight, so my intention here is mostly to gather information so i hopefully do the right things when i eventually can afford to have the work done. It will likely be a while still.

Seems to be a replacement crystal as i could not see any symbol.

I did a quick polish with toothpaste and it worked astonishingly well! But the deeper scratches i think would need to be wet sanded out, which seems too invasive to me.
The scars do carry sentimental value, and i'm wondering if it might look a little off with a pristine crystal together with the battle scarred case.

I suppose i should also ask if anyone has a rough value estimate? Let's maybe assume it is in running order, how would the other good and bad aspects of this particular watch affect its worth?

I live in Germany, close to Potsdam and Berlin.

I would contact Robin Israel if I were you, he is not cheap but I have heard he does a great job.

Forget the balance here. Too much work to fix it. There are 2 complete balances on eBay in the moment. Around $110. Plus shipment from USA . Still much cheaper than work on the existing disaster. Easy swap job for a Watchmaker. There are quite a few good ones in Berlin. Don't wait too long, buy is very soon. That is something many are looking for.....

For me, the key point here is you don't think you will wear the watch. Since your budget is tight, I would just hold onto it and not spend the money to repair it. You could also get a strap and wear it around the house, just to experience it, as is.

Hello, and thank you all for the very helpful replies apologies for my slow answer. I will keep a look out for a complete balance assembly and get it to a watchmaker when my funds allow it.
However, i struggled to find the right parts on ebay. I even searched when watchyouwant first posted this. Might have already been sold by then. I didnt have time to reply at the time and i then forgot about the thread (i forget things..), so my apologies for that.

Is it correct to be looking out for a balance specifically for the 286 cal movement? Any variants i should be aware of? Or did they use the same balance assemblies in other movements also perhaps?

It is good i posted this. Turns out, this watch is not that special which is good because like i said, i'm not that into watches and i dont use them personally. But i am sentimental, and i appreciate mechanics (and what could signify fine mechanics better than a swiss made mechanical watch?) as well as mid century and functionalistic design.

So i think i might do what Philips suggested actually. Get a strap and see how i like wearing it round the house. I don't like most straps so i think i will just NATO it. Might be wrong for its time idk but if my grandfather broke his original strap, i think he would DIY his own NATO in a pinch, and end up keeping it like that.