Help with history of watch

I have an Omega Constellation Pie Pan, Movement 505, screw case 2887 serial number dates it as 1956. I'd like to know if it's original or has been altered and if possible a value. Thanks for any help.

+1
Though the overall watch case appears fine (case front and back are in good condition), the watch is significantly devalued by the re-painted dial. Feel sad to say that.

+2
Nice case, caseback in good state. Ruined dial.
I can only see someone buying it for parts.

I am new to OF. I appreciate the expertise offered by Members. Since I am a novice, how, or where, can I purchase a "nice" vintage watch like this without getting ripped off or garbage?

I think this is a bit over the top, this would make a fine watch for anybody except us Omega nerds.

There's a term we use called "buy the seller" which means just to do research on feedback, online reviews, whatever supporting evidence you can find that the seller is trusted and offers a good return policy. Many watch sellers are NAWCC members (National Association of Watch and Clock Collectors) and offer a no questions asked 3-day return policy, and that's also become somewhat of a standard for sellers in general, tho among the collector community primarily. Pay with a method where you have some recourse if things go sideways. Get condition and originality statements in writing. Post potential finds here if you are unsure as people are always willing to help you evaluate a piece. Luck plays a role as well, but not as much as experience or research.