I just got a new set of 6L6 tubes for the Herbert.
You guys should really jump on this deal. Tube Depot supplies mass quantities of Winged "C" tubes to amp builders. If they plug em in and they don't match as a set, they send them back to Tube Depot. Well TD puts em back into matched sets, then sells them to you. So you get perfectly new, good working tubes, that just have claw marks on the bottom from retention sockets. I tested them out, and sure enough they all biased out perfectly with one another.
Here is the link.
http://www.tubedepot.com/sed.html The 6L6's usually sell for $55 a matched set, if you buy the seconds you get them for $20 a pair!!!! Jump on this deal while it lasts fellas.