They are fairly common here and 617 to 616 is same as 6498 to 6497. This particular one is from an old Cortebert wrist watch rough shape unfortunately.
![Image](https://clickpix.org/images/ZzMHUt.jpg)
it's a Radiomir Black Seal, the whole watch is bitten a bit, but I'm going to re polish it myself...
Madness!!! What a collection even with a Cort 618.
I have one use gen non alarm main plate incabloc (White Angelus Dial) with Jorge convert bridge.