Need some help vintage omega

The watch looks legit to me, with some obvious condition issues. Not a watch that most collectors would find appealing, but not terrible. I don't know what currency "450" corresponds to, but assuming it's USD, Euro, or GBP, it's not a crazy starting point if the watch is running.

If you like it, make an offer that you're comfortable with. I really have no idea what the seller would accept. You can also use the eBay sold-items search function to see what similar watches have sold for recently. Keep in mind that you might have to pay to have the watch serviced.

Which would primarily be the polished case and the rather tired dial.

If you haven't read this you should find it quite helpful in your search for a nice watch.

Looks pretty terrible to me. If I wanted it, I might be tempted at 150, but to be honest I’d much rather pay a bit more for a better one.

Dont buy it not a good example at all- dial is poor and you will not enjoy looking at it. Keep researching and looking these are quite common.