The serial number is surrounding the large gear on the top of the movement. It looks as if heavenscloud made it out to start with 117 which dates it to sometime between 47 and 50.
Your watches model number is 2487-6. If you google that number with omega watch you should find some other brothers and sisters to your watch.
Unfortunately the Omega vintage database,
https://www.omegawatches.com/planet-omega/heritage/vintage/, didn’t get a hit on this model. That’s not unusual as their database is know to be incomplete.
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