Looks like a genuine Omega bracelet for a vintage Mark IV with hooded lugs. No numbers on the end links as far as I know because they are integral to the bracelet, not sold separately. And yes, those end links are just rolled steel, but that’s how they were done back in the day and how Omega still makes them for replacements. Since it is not in a sealed Omega package, it really isn’t new as the seller claims, but used. Price is about right for a new one from an AD, but I wouldn’t pay that for one out of the package.
do you have a Mark IV? Because if you don’t have one or a watch like it (this might also fit a Flightmaster and a Mark III) you really can’t use it for another watch — those end links are part of the bracelet and can’t be removed without forcing it apart.