Hi and welcome here!
Beautiful watch, congrats!!
1. Bring the watch for service and crystal polishing / replacement to an independant watchmaker.
If you let us know where you live maybe you can get some recommodation here.
Do not send the watch to Omage
2. watch should be produced between 1966 and 1970, reference number would be 145.006 or 145.016 either with 321 or 861 movement
3. Do you look for an metal bracelet? If yes a 1116 Bracelet with 548 End links would be correct
Nice reading here:
https://omegaforums.net/threads/145-006-145-016-seamaster-chronograph-research-thread.77145/Click to expand...