Need help identifying this watch

I need help identifying this early Omega watch. I purchased this watch about 12-15 years ago from a small independent jeweler in Santa Ana, California. I liked that it was different from the other vintage Omegas I usually see.

What is the caliber number?

What is the approximate age?

Any other useful information?

Thanks for any help that anyone can provide.

Dan,

Thank you for your response.

The movement diameter is 19mm

The case dimensions are 22mm square (not including the crown or lugs)

The lu to lug measurement is 30mm and it takes a 20mm wide strap

Phil

Thank you.

CK 3658 is my best guess. Here in a 1940 French catalog.

I confirm caliber 19.4 inside and the redone dial.

Thanks I didn't realize that the dial had been repainted when I bought it. I had just started getting interested in vintage watches and didn't know what to look for or what questions to ask. I had been given a couple of my fathers old watches by my mother after he passed away. One was a Longines tank from the 40's and the other was a Hamilton from the early 50's. I had also just purchased a early 60's Omega Seamaster about a year earlier. I've got a half dozen vintage dress watches and another 10 latter model sports watches now.

I'm not that worried about the value of this Omega. I bought it because I liked the way it looked and that it was different. I would like to get it serviced though if you can recommend someone. I used to live in the upper back bay but moved to Arizona when I retired and don't have anyone around here that can work on it. Also, when I opened it up to take pictures of the movement and case back I ad a little accident of sorts. The minute hand must have been loose because it flew off somewhere when I took the movement out of the case. I spent several hours on the floor with a flashlight and magnifying glass looking for it but with no luck. That will also have to be replaced now.