Dear all, I have my grandfather's vintage Omega with a 561 movement from around 1960 and I would like to look into fixing it up for when I hand it on to one of the kids. There are a couple of obvious issues: someone has wiped the glass with something abrasive, the crown doesn't match and the strap is not original. I'd be grateful if anyone could tell me more about the watch, whether there are any other issues that could/should be restored and what the likely costs would be. I'd also be interested to know what the written markings on the caseback indicate. Many thanks.