Anybody see this? I think it's in Norwegian or something. But it looks like 4 6LU8's used in push-pull fashion daisy-chained to make 2x12.5 W and a nice looking square wave. I realize we're aiming for 2 tubes single-ended, but I just wondered if this helped at all.
http://www.veiset.net/6LU8/index.html
Note: Also, while poking around the web, I saw someone comment that he thought the power part of the 6LU8 was more like the 6W6, and someone else commented that the 6W6 was a very under-rated tube for stereo amps. Just thought I'd toss that in there. You guys can feel free to tear it apart if that's not true.