Spotted a Constellation 168.029 up for auction - I was interested in the bracelet, which didn't look familiar, but then I spotted a reference to it in an essay by Desmond (see ad below) which I think he says is a 368.4076. Unusual, as most of the bracelets Ive seen with these C cases are the 1040 brickwork variety.


In the end, the 751 movement pics made me pass, partly after reading this very helpful post by @Archer
https://omegaforums.net/threads/spotting-problems-with-watch-movements.36339/
The dark circle on the caseback might indicate a worn rotor pinion, as he mentions in his post, There are also a lot of black spots/dirt visible.
Both of the above suggested it was in dire need of a service and maintenance -


the cost of which might grow due to replacement of old parts etc. The net result would be the same price as a serviced version with guarantee from a reputable dealer (albeit without the bracelet.)
For future reference, I'd be grateful for any thoughts or advice if I was wrong about the movement issues!



cheers
Dan