I have searched high and low for parts for these amplifiers. Your best bet is to look for a parts unit or someone parting one out on ebay. I own a KA-9100, KA-8100 and KA-7100. They are all great amplifiers, but the 9100 is very special. The dual mono design gives a big open soundstage and it is more coherent than most amplifiers built today. If this amplifier was built today it would cost thousands.