WA6 combinations are many. My favorite setup was the 6DE7 with a metal base GZ34 rectifier. Once I got the HD 800 I went with more power on the drivers-- 6SN7 with adapters.
If that's too rich for your blood (a metal GZ34 can cost up to $300) go with the Sophia Princess as a starting point.
Of course there's always the 596, if you can find one-- I'm still looking for a matched pair.
For WA6, you can skip the 6SN7 and get a pair of 6FD7. Mullard metal based GZ34 with Sylvania 6FD7 is my go to tubes for HD800.