I just couldn't resist so please help!

[Rogerg]

I bought this 18k cased small second watch today from an auction I trust with no more info than what I've stated. Yes, I know that isn't wise, but it seemed to be a decent price, and I was distracted while simultaneously buying another watch. All that said I was wondering if anyone here recognizes the case type as I've not seen this back before? I'll have it in a week or so but if anyone can tell me what this might actually be in the interim, I'd appreciate any info!

 

[JimInOz]

Could be a locally cased variant, where did it originate?

 

[X350 XJR]

Likely a caliber 510.

Looks like a hallmark on the side of the lug.

I have seen this case back before on an Omega case, just don't recall the reference.

 

[Rogerg]

Thanks for the replies! I'll know more about it when it gets here.

 

[Rogerg]

It arrived yesterday and I'm quite pleased with it so far. It seems to run well and keeps time with my Eco-Drive which is my benchmark not having a timer. It ended up a Ref. 14367 and having a caliber 302 in it for which I am finding almost no info on. Here are a few quick pics...