I really don't know what's the situation where you live, but at least here the basic options that aren't really pricey are for instance JJ tubes and Electro-Harmonix plus Sovtek.
Preamp: I don't really think/find there are huge differences in tubes used, as long as they are the right variety, *except* for the 1st input tube amp. You'll want to use the best available tube for that...crap tube there spells buzziness and an evil kind of cold fizz in overdrive.
I've been really happy using Sovtek Mil-spec 'everlasting' tubes for preamp tubes everywhere but the first slot, where I try to get a real good tube - currently a 60's Telefunken...anything _but_ a hi-gain tube or a cheapo tube. I hear them Tung-Sol Mullard copies are good; the first series had quality issues but they should be more stable now.
JJ 12ax7 'S' tubes are kinda nice&warm, and cheap here.
Power tubes may have more of an effect overall...but any matched pair seems to work just fine. Mine are mostly TAD, JJ or Electro-Harmonix. I have a bunch of Sovteks as well, also mil-spec but they do sound a bit cold IMO.
Far more important than tube type is right biasing, however.
So my recipe is get as good a 1st preamp tube as you can and just nice sturdy tubes for the rest.
I have maybe 40-50 pre-and power tubes I've tested every which way to arrive to this conclusion. No doubt you _can_ detect differences with better tubes in most any position, but IMO it's such a small difference it's not really worth the hassle. Can't always be using matched pairs of same age anyway...chances are, you get some superb vintage etc. tubes and blow one the first gig, and after that you have a mismatched set anyway.
So go for reliable tubes, but NEVER underestimate the importance of the 1st tube the signal sees in the amp.
Just my 2c.
