Can someone help me identify this ~1930s Oyster Perpetual

[dbcooper]

New to the forum (made an account to pose this question really so apologies if this is the wrong way to ask).

This watch was purchased by my fathers uncle (grandad?) during his stint as a pilot during the second world war I am told, he led quite an interesting life and was indeed a pilot so this all stands up, and leads me to believe he wouldn't buy a counterfeit watch. The band has been sold on (unsure when) and the watch has lived in my fathers drawer since. No papers or anything, just the watch without band. I have taken it to the jewellers the family uses and he was certain it is genuine, the weight is correct and the movement is still as sweet as ever, when it has been lying dormant for a while and movement stops simply picking it up and giving it some movement triggers it again which I imagine is a good sign ?

What puts me off however is a lack of serial numbers between the lugs, I have never had the watch opened however to know what is inside. The bezel pin is also silver rather than gold, it was at one point gold with the crown but has chipper off, does a gold plated bezel pin seem suspicious ?

I love the watch regardless, it works and looks great whilst being understated so I can enjoy it without looking like im trying to flaunt a Rolex, my curiosity has just been getting the best of me recently and as I needed a new strap (leather if anyone could point me where to get another) I thought I would investigate some more.

Any info is helpful, thanks in advance !

*I cannot yet post links, am I able to reply with a link ?*