Seadweller clasp question

[allegedly]

Hello guys, Rob, newbie and novice here.
The spring bar (I think thats the correct name) that holds the folding clasp to the link bracelet on my old seadweller (circa early eighties ) has worn to the point of needing replacement. I live in the sticks in the far North West of Scotland and the local jewlers do not have any that fit. The stock ones they carry are all too big (fat).
Do Rolex make a special, slimmer size one for this fitting? If so, I'd be grateful if anyone could tell me the correct part number and where I can order them online here in the Uk?
Also, is there a parts diagram book of the watch in question in pdf or similar I could download for information purposes? Clearly, I'm not a watchmaker in any way shape or form, but since I found this site, I'm developing an interest and that seems a way to gain knowledge.
My apologies up front if these seem rather naive questions to the more experienced among you but I guess I don't know any better...at the moment!
Thanks for a great forum
Regards
Rob