: I have seen some unsigned 773x movements in Heuers of the time, but
: I think these may have been transplants. If signed for another
: manufacturer, I believe that probably removes any doubt any it
: being a transplant.

Thanks everyone, it was a rare Autavia Bund 73663 (albeit with incorrect hands) so I was tempted to just buy it, but unfortunately if the movement is replaced I will pass!
So glad I got a pic of the movement before making payment, and thank you!