Help needed authenticating a Seamaster (ref. 14389-12-CSP)

Hi folks,

Got this a long time ago from an antique shop, didn't cost much. As you see, it's got plenty of patina. I've done quite a bit of google forensics, and have found near matches, and one exact match except with golden dials and hour markers (shapes and text placements etc. all were exactly the same). Is this genuine, or does it belong in a beach somewhere? Do you see anything funky with it, other than the condition, anything that looks replaced or like a mismatch? If it's cr**, just say it's cr**. I am no aficionado, so all info appreciated. Also, I'm curious, what does the "12" in the reference nr. refer to? Thank you!

Identifiers:
- It's a hand-winder
- Case reference nr: 14389-12-CSP
- Serial: 18681615 (serial number decoder came up with the year 1961)
- glass feels plasticky
- case measures at about 36mm

The amount of replys here has probably answered some of my questions 😁. Still, any input is helpful. What might be obvious to you, is news to me 😀

Also for me everything looks ok..

Thanks guys, good to hear. I'm also curious about the areas around all markers. I haven't found anything similar online. Really wonder what happened there? Sort of looks like how corrosion spreads on contact points, but in my mind rust is, well... rust colored. Perhaps someone knows, or could make an educated guess (attention metallurgy experts).