Maple Leaf:
Why look for new tubes for your gear? Do you really think that tubes that are all built to the same specifications really sound different from each other???
The whole tube game is a scam. I have taken them apart and they are all made of the same crap ... copper/tin/solder which I know was all purchased from the same sources. THEY ARE ALL THE SAME. They cost pennies to produce and then they want us to pay ridiculous prices ... it is all BS.
Spend your money elsewhere, on something that will make a difference in your system, for instance, like on good cables.