It looks to me to be a nice "Omega 30", a generic term from the diameter of the caliber (265). Before the late 1950s not many Omegas had model names.
The 265 movement was introduced in 1949, the serial number places yours at about 1950. It is known as a manual wind, sub-second movement.
It was cased in the UK by Dennison as many Omegas of that time. This was usual practice to import movements and case them in the destination country due to import taxes on fully assembled wrist watches and other similar regulations.
It looks all original to me except for the crown which may have been replaced in one of the many services it has obviously had.
Although yours isn't in pristine condition, a sympathetic clean, oil and adjust servicing should provide you with a very nice Omega.
The 265 details (30 T3 PC AM 15 p) mean base caliber 30 version 3, Shock Protected, Anti Magnetic, 15 jewels.
I think
@MMMD has some similar watches in amazing condition.
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