From what we can see it looks to be a good Mk1 Jet. Crowns should have the logo and be crosshatched. You can find a little more out here:
The strap is the perfect touch. Stirling had his own custom made. Skeleton to the extreme due to the propensity of fires in the race cars of the day.
Didn't use the Graph much, maybe only one race. His preferred watches had a ratttapante movement for lap timing purposes.
Well, you say it was cheap. Jet dials and hands do turn up. Have your watchmaker examine the watch to see how the movement is. If it is good, then you can track down the correct parts and have them fitted.
Are all Enicar Sherpa Guide cases interchangeable? Excepting the later "pillow" cases, of course. I've bought a Mk1 Guide with a pretty big dent in the case and wondered if I could use a later case as a replacement. The backs are visually different but I think they might be interchangeable...
Looks very nice to me though I am on my phone, not my desktop. The back especially looks to be free from the usual gouges from trying to open it without the correct tool.
Here’s a link to a similar watch:
Damn, got us where you want us. Probably holding out for:
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Yes, old bracelets are no match for today's. Better materials, better design tools, better manufacturing techniques. Old bracelets are OK for display, not for wearing.
You forgot to tell us where it came from!
Going by the logo it is from the 70s. The specific model is the 165-54-01 (engraved on the back). If you google that number you'll find images of similar watches. Some, like yours, with the newer logo (two rings around Saturn), and some with the older logo (single ring).
Can't help you with...
I’ve had a few vintage watch strap clasps open at in opportune times. Nothing disastrous, thank goodness, but enough to put the fear of god in me. I use modern BOR, modern tropics or NATO straps and save the originals for display.