Funkstrat's link in the other Classic 30 post has some good tube selection explanations in it.
I use Sovtek 12AX7WA's in mine, but that's the opposite of what you want lol.
Read that doc, it will explain a bit about how the amp works. The tube in V1 position really shapes your clean sound, but a lower gain tube there will impact your drive channel (V1 is always in the signal path).