I just tried Jules Borel for you. It shows the watch by case number and movement. However, the correct crystal is unavaliable and it shows with a generic part number:
OME CS#6304
OMEGA CASE REFERENCE
OME 550
CRYSTAL SUB L 297 0.00
My guess is that these crystals were never signed and that there is a good chance the one on your watch is orginal.
gatorcpa
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