Can’t buy output tubes anywhere except from manufacturers at high prices.

RAM Tubes is still selling expertly-tested, labelled, and matched tubes. 

@mulveling Thanks, that's good to know. My tube amp (DeHavilland 50A) was voiced with Gold Lion KT-88s which as we know are becoming difficult to source new. Then there are the tubes of Chinese origin, Viva sells Psvane and Linlai, although they are not currently stocking any Linlai KT-88s yet even though Linlai makes several versions. I am using a Linlai 6SN7-E in my DeHavilland preamp and am pleased with its performance so far and this has piqued my interest in their KT-88 tubes.

BTW, I find your posts to be very informative and delivered with decorum and civility, so thanks for that as well!

I wonder how much sales have been affected by the tube shortage for audio manufacturers that specialize in tube equipment?