Re: tube sockets and plugs for the new tube curve tracer
I wouldn't call it a proper "source", but the last 7-pin socket saver
I got was from Jim Cross @ http://vacuumtubesinc.com
I had to send him a note specifically for it, and he scrounged a
reasonable one up out of hits back room.
They've currently got a couple listed, but they aren't cheap.
His email is firstname.lastname@example.org
(No affiliation, satisfied customer, yada-yada-yada)