Hi,
As far as interchangable. I have looked at a few models and and each service manual seems to have a different part number so im not sure. Let me put it this way on Ebay the price is crazy! People who have broken units almost give them away these days. Around $100 is about it.
Working on the part with Tascam Ninja right now. Hope he has it at a resonable price.
take care.
Forgot to mention; I called Tascam in Canada and they don't have a listingfor the part number. Not looking good.