I think Omega charge around £200 to replace the bezel. Prior to the Swatch Group parts restrictions I was buying them for around £185 but prices for remaining stocks have rocketed so it's cheaper to get it replaced by an Omega accredited repairer who has access to parts.
Trying to refinish these bezels isn`t always successful, even if the insert's in decent condition. Once the bezel's picked up deep scratches and gouges it's impossible to get it right. Light scratching can be corrected with minimal loss of sharpness, but some loss of edges is inevitable and it's something to look out for on these.
I`ve serviced and sorted lots of these in the past. Usually a scruffy bezel's a sign of a watch that's had a busy life, but given that some of these watches are 20+ years old it's hardly surprising.
Omega charge around £350 for service and refinishing, but if the bezel's beyond refinishing it'll need replacing. They can`t force you to have it replaced but I`m guessing they won`t refinish a bezel that's too far gone.
Paul