[Arran]

For newbies and others, a lot of us bought some of these when they were only $15. That was when he sold about 1300 of them.

http://www.ebay.com/itm/151325245645?_tr...EBIDX%3AIT

They are good tubes, but they are 6E5s with the big pin base.

Still not a bad deal at $20. Takes a couple of weeks to receive them.

Russ,
  One of the problems with the 6X6s is how they are mounted mechanically, in most cases you could fit an adapter to use something like a 6U5 but on some Rogers sets there isn't enough clearance to fit. So what I have used are some 1629s I bought a few years ago to use as a substitute for 6U5/6E5 tubes with an adapter, ironically. But like the 6E5s the 1629s are single shadowed and the 6X6s were double shadowed.
Regards
Arran