In the UK you could try,
Herts, CM23 5LT
ph. 01279 755862
KL Camera Repairs Ltd, Rayleigh Tel: 01268-775781.
I have not used them but have read they have a good rep.
I have used and can vouch for,
Jurgen Kuschnik http://www.jurgenkuschnik.com/
but he's in Germany.
Hope this helps,