Help to identify a pocket watch

I am new to this forum and to watch restoration (I would not dare call what I do watch making). I have an older Omega Pocket watch. Not much to go buy but is in very good condition, which makes me wonder. When I got it there was a case screw missing and the ratchet wheel was installed crooked which caused it to rub against the case closure (no damage was caused to the wheel). It also has an exceptionally clean face. So I was a bit unsure how old this really is and what was done to it prior. After disassembling and examination the only thing I could find that was broken was the mainspring.
It is case number 5043855 (1913-1918) and movement number 5077085 (1916-1923). Years I specified may be off as I saw differences in different tables. But probably close.
It is .800 silver, and I believe marked as German. T
There is a small mark that looks like a bird or something on the edge of the case (see picture) cant be sure what it is it is so small even at 25X.

Any help in identifying the model and whether it is pieced together or an original Omega?

Thanks everyone.

Thanks for the info.
The diameter of the main plate is 40.63mm.
Here are 2 photos front and back. I assume that is what you ment. I didnt install the movement yet but laid in the dial and hands for viewing.
Thanks again.

Thanks for the info.
The diameter of the main plate is 40.63mm.
Here are 2 photos front and back. I didnt install the movement yet but laid in the dial and hands for viewing.
Thanks again.

Nice watch!

I may have made a mistake on how I measured the movement. I measured it again from the dial side and it is 39.15mm.

I keep wondering how the dial can me so clean in a watch as old. Had me thinking it was a new dial, but who knows.