Another recommendation for Bob at Eurotubes.
My tube amp developed a problem a couple of months ago and it will not turn on. I remember reading online that Eurotubes is a good place to deal with. I looked them up on the internet and was surprised to find out they are here in Portland (they are in Milwaukie, which is a suburb of Portland). I called them up and went out there to get a couple of power tubes. Well, turned out that was not the only problem. I called them back and they told me to bring my amp out. They put in a new rectifier tube to see if that was the problem. After they made sure that fixed my problem was when I paid them, for the tube only, no charge to figure out the problem with my amp.
I'd go back to them again if I need tubes for sure.