Ram Labs chief Roger A. Modjeski is an Audiogon member. His screen name is Ram1. He designs some nice tube gear (Music Reference). You can probably email him through Audiogon and ask him yourself about how he tests his tubes and where he gets them. He is a straight shooter.
A lot of information is available at: http://www.electron-valve.com/
His website is: http://www.ramlabs-musicreference.com/
See this Agon thread with his comments as well.
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1015363401