BEL was located in Northern California for many years and may still be there. Richard Brown is NOT an easy person to contact however, your best bet is to have a BEL dealer in your area obtain information for you (if THEY can contact the manufuacturer). That said, if your amp is the 1001 it has gone thru many upgrades in 15 years, now designated the Mark 5 I believe. I also think that all upgrades are available for older models and each makes a significant improvement on its predecessor. It is an excellent sounding piece and would probably be worth your effort to upgrade and repair if financially logical. I owned a 1001 Mark II for many years...still miss it!