Hi Sally,
I'm sorry to read of your problem, maybe we can help a bit.
As Lorenzo says, there are many different, but similar Seamasters from that period.
I have a website with some older Omega catalogues from that period www.Old-Omegas.com
Maybe you can find a match there ( I have tended to ignore gold/dress watches in some of the catalogues though - sorry )
Another possibility may be that the Jeweller has writen down some Info about the watch.
Useful info are the following.
Movement type :- ( a 3 digit number )
Movement number :- ( an 8 digit number - this can also be used to "date" the watch )
Case type :- probably a 6 digit number with a dot in the middle. ( I say probably because Omega changed their system around the start of the 60's )
With these 3 numbers we may be able to find a picture or at least give you more details about the watch.
Finally, If you really want to find a "replacement". I'd start looking in eBay. there are literally thousands of Omegas in eBay. It is probably the best online database in the world now. Even if you don't use eBay to buy, it contains so much Information ( which changes weekly ), you may find a exact match for your watch, which contains at least pics, maybe some more detailed info & will give you an idea of the price.
Good luck & If your Jeweller can provide any numbers I'll see what I can do.
All the best
Steve