Quick Ebay search and there a many like this coming from there. Verify the seller is legit, some shady sellers in that part of the globe with minimal recourse. I have passed on some lovely watches that have gone for a steal simply because I am afraid of the risky sellers. You may want to see if anyone here has experience with that seller.
This is true! I have seen other sellers offer similar looking watches.. even the photos looked similar .. but didn’t think much of it! Seller: timebit24
Are these redials the real Omega bracelets, cases, hands, markers and movements but just the dial is replaced?
Any glossy black dial on a vintage watch has a relatively high probability of being a redial. I would inquire of the seller directly on that point, ask if there is a return policy, and also see if he/she has buyer reviews. If the watch is authentic and not a redial, $500 is very reasonable.
Usually genuine Omega case/movement, heavily polished up to look shiny and given a nice new paint job on the dial.