I'm not sure if you really want to buy used amp that runs VERY HOT. Units that run on high temperatures usually dry out caps and fail faster in general as well. Repair of the high end unit may run into high dollar bill if you don't know specialists that won't rip your arm and leg. Believe me ones advertised here or even recommended by community either money-no-option types or so far away from you that shipping of such heavy unit as Krell will run also onto the high dollar bill. DIY refurbishing requires some knowledge of electronic circuits -- especially testing elements.
If I were you, I'd look for powerful class D amp such as Bel Canto Ref1000 monos and bypass vintage or older Krells.
If I were you, I'd look for powerful class D amp such as Bel Canto Ref1000 monos and bypass vintage or older Krells.