Hi Graham,
Here's a bit of Info that I found.
Firstly I checked my Omega "dressing components catalogue". This lists crystals etc, unfortunately mine is dated 1983 & your watch is not listed.
Next, I logged onto the Jules Borel Website and looked up your case Ref. 168.0057.
The have 2 crystals in their parts list but no prices. ( usually indication that it is not in stock )
One crytsal is listed as having the Part number TN5222 ( note only 3 twos there ), The other is SN0337
For each crystal they also list a bunch of other watches that use the same crystal. Here is the list for SN5222 :-
166.0195
166.0196
168.0056
168.0057
168.0064
191.0041
191.0042
198.077
198.080
366.837
391.019
I checked these in the "Dressing Components Catalogue". I found matches on 3 !
166.0195 => 063 TN52222 ( Note 4 twos here ! )
166.0196 => 063 TN52222
168.064 => 062 SN 0337
So it's pretty clear that these seem to be interchangeable. I'm afraid I know nothing about Omega crystal codes, so can't tell you the difference between these codes. ( SN = Saphire ? TN = Toughened ? a pure guess there )
Hopefully these codes can be useful for you. I'd actually try Jules Borel directly .... they may have stock that is not listed on their website.
If it doesn't work out with Jules Borel, I could also recommend another great source of Omega spares in the USA ( per E-mail ) or you could try Cousins in the UK - their website is sometimes slow to load :-(
Good luck with your search & let us know how you get on.
All the Best
Steve
