They would appear to be different watches - the one James just linked has an incorrect crown, steel and too small, whereas Stewart's has a different, again incorrect, crown.

It's something we've been seeing for quite a few years now. Manual second gen Carreras, almost always 73655s, with unsigned Vj 7736 movements, typically of a slightly lower grade than Heuer was usually buying in. Quite often originating in Eastern Europe.

The parts do seem correct; dial, case, hands etc. I have seen some of these in the metal, and the model ref and serial numbers are stamped correctly. The serial numbers are period correct and fairly early - I didn't take note of the serials to check whether all are contiguous but they don't seem consistent with a later service batch. None seem brand new either - quite a few are well preserved but all show at least some wear, often to the plating on the case.

So it's something of a mystery really. If someone found a large batch of parts for these and is creating them, then they tend not to use NOS cases, at least. On the other hand, it's unusual for Heuer in this period to use unsigned movements. I wonder if this was the watch they used in the difficult, but not entirely impenetrable Eastern European market of the time, and scrimped on the movement? Not entirely implausible I guess.

I'm a bit torn really. As a buyer, I'd be wary but not totally dismissive - if any other parts bar the movement (and perhaps the crown, manual wind movement and plated crown means quite a lot of those seem to have been replaced) is wrong, walk away. If otherwise ok, then I guess worth thinking about if the price is right.