The seller says that it is an Omega Seamaster cal. 751 ref. 166.036
I hopped on Omega's Vintage Watch Database and using the caseback number and calibre I searched in vain but couldn't find it anywhere. The closest I got was this Seamaster Cosmic. However, the movement and dial are still different.
Is the watch in question a mash-up of various Omegas or is it an original? I've exhausted my watch knowledge and thought I'd ask the WUS community. Thanks!