Hello!
Interesting idea and unexpected solution.
I'm afraid the main difficulty is that even if you are ready to live 6497 (or its derivative) movement., Suppose the caseback may also not be correct, then you can make a custom-made watch face and hands. You can do the same with plexiglass. But the point is that you need a rather specific case, which can only be taken from 372/605/606/557, and finding this case separately will not be easier than the whole watch.
Alternatively, you can search for a cheap DHgate pam, in any new 1950 47mm case. Although they are worse in quality, they are quite similar to the truth. Here's an example like this:
https://a.aliexpress.com/_9Rd9hA
only without engravings, usually they should be around $ 100 - 120,. however, be prepared for the fact that the engravings of CB and between lugs will most likely be incorrect, also do not buy an automatic watch for movement. to fit correctly.
Then you can put on a solid caseback, and put on an individual watch face and hands.
But to be honest, everyone who wrote above is right. Finding M2M will be easier and cheaper. I'm sure you just need to be a little more active and constant in this search. 372 are sold regularly.
