Can't say much from one photo, probably genuine.
Would need to see inside the case back and movement shot to say for sure, couldn't give a valuation either.
https://omegaforums.net/threads/a-large-23-4sc.29526/
Marking on the case back looks South American, a Swiss case would be marked on the inside.
Indeed the watch is in Argentina , mabye it is cased overthere. I know it is a manual winder.
But it baffles me to see one in solid gold.
what is the diameter of the watch? I doubt it is a 37mm goldcase...
Sadly a lot of fakes and Frankens coming out of that part of the world...
And there are many fakes in the omegamania catalogue...