$6500...that is a tough call. Personally, I would return and save up for a better example, as that watch will very difficult to sell in the future. You have a $6500 or less Franken...up to you. It doesn't look too bad.
If you are looking for a collector piece, 1. Absolute correct parts 2. Unpolished case + no dings 3. Tritium intact + lovely patina 4. Flawless dial 5. A safe to store it and forget about it for 10 years. Based on what you have got, I think I would just wear it as it is and dont worry about anything else. Parts alone it is already worth more than 6500usd.
The movement is working very well and the dial is not re-lumed, it is a beautiful dial with a dark brown overall colour. Thing is, I bought it from a local collector and was sure that everything was correct till I opened the case and saw these after several weeks and was very upset initially to see the watch was not all correct. I need to re-make my mind now to whether keep it or not...AND I can't figure out why on earth that part would have had to be changed at all, it's not a moving part which wears out is it?
The whole movement, with the exception of the chronograph bridge, might not even be an Omega one. Let's see if someone is able to spot another pair of clues in this direction.
Comparing it to the online 321 pictures I don't see major differences except few curves on some parts. Did they ever make a fake 321 caliber at all? Or is there another movement same size as the 321 to look similar and fit into this case?
This one I just found online, has no caliber stamp and no "adjusted" or "unadjusted" with high serial number. Still Omega though?
The 27chro c12 is a movement made by Lemania and branded by a number of different manufacturers. https://www.watch-wiki.net/index.php?title=Lemania_2310 Omega Tissot Lemania Patek Breguet ...and others, all used the base movement.
More, https://www.revolution.watch/the-lemania-ch-27-to-the-moon-and-back/ So the movement could be from another brand. It will generally fit and work just as a 321 does, but that doesn't necessarily make it an Omega 321.
I see, thanks. The bridge and the two other stamped parts will make it an 321 then, and this one only has the bridge so yes it may originally have belonged to another brand. It still is not a "fake" movement though, which was what I was trying to be sure about.
Any ebauche derived from Lemania 2520 is able to make an Omega-like caliber 321. But it is not a real Omega caliber 321: there are still subtle differences.
