need help on buying vintage seamaster on ebay

www.ebay.com/itm/191402876003
www.ebay.com/itm/121536209727
These two interest me wanting to pay $400 just want to make sure they are authentic any insight would help thank you

Both look fine from an authenticity point of view. For that price, I'd be wary of buying a gold filled watch unless it was pristine. The fill is worn off the lugs in one of them quite badly, certainly not something I'd pay $400 for. Look for one in steel IMO. You should be able to get something decent for this price and you don't have to worry about gold plate wearing off.

FWIW though, my first vintage Omega was a gold filled Seamaster, much better condition than these but still a tiny bit of plate wear on the very edge of the lugs. It just sold for $443 US on the Bay so maybe that's the going rate now. I bought it in 2007, also on eBay for $120 so it appreciated pretty well really. I never wore it any more but it was pretty hard to pack it up and send it off 🙁

Thanks for the opinions I will start looking for a ss omega vintage I think that's the going price for the automatics nowadays. I will be on the lookout and post them thanks again