A couple of years ago I asked AP's help in sourcing a good repairer for a Pentax S1a of great sentimental value to me. Ivor Matanle replied -
"From personal experience I can recommend D. Bharadia in West Croydon, who recently did a magnificent job repairing and setting up my Minolta SR7, which is of similar age to your Pentax. He can be reached on 0208 689 1887. Tom Page is also an expert repairer of SLRs (although with a speciality in Exakta and East German cameras) who seems to make almost any camera look pristine. He is in Watford and can be contacted on 01923 800588. Or try Ed Trzoska in Leicester on 0116 2674247, also a specialist in repairing classic cameras."
Unfortunately, shortly after receiving this reply I encountered an employment-related cashflow shortfall scenario(!) and am therefore unable to add a personal recommendation of any of the repairers listed. Should you try any of them out please let me know how you get on.
All the best,