https://www.omegawatches.com/planet-omega/heritage/vintage-details/15790/ Obviously stainless, not 18K gold.
It looks to have an issue as the regulator in your movement photo is off the scale. What else do you want to know? The case back has the reference that @efauser linked to so, it should be that. Are you asking about originality or condition? Cheers, Chris
You need to be clear about what you want, if what I provided isn't enough. "any other ideas?" is pretty vague, don't you think?
The regulator arm shouldn't sit outside the graduated lines between A and R on a well kept watch. If it's keeping okay time where it is, it's a sign that it was moved there as a quick fix. The watch went past its due service date, and instead of getting a full service, somebody moved the regulator. Have it serviced as soon as you can.