I had an HSE medical in 2000 in Newcastle (Jesmond), think it cost about £120, I can't rememer the name of the Doc of the top of my head but could find out if required. A right miserable faced bugger though
Anyway, aren't most agencies self-declaration these days? If any (BSAC) divers need to see a medical referee you can get that done for about £15,(I know of at least two medics in Newcastle that charge this) guess it'd be available for other agency divers too
Correctomundo, BSAC Branch Instructors don't require an HSE medical, but I believe the BSAC School Instuctors do (ie these organizations charge for courses).
Also the costs of BSAC instructor courses are nominal in comparison with PADI, presumably because a PADI course allows you to earn money from your diving which, unless you go into instructing in a School, you won't with BSAC. although PADI Instructor friends of mine have told me what they earn is a pittance.