I started with Rodger's low noise matched tubes, they are overpriced and uninspiring garden variety Russian 6922's. Five years ago they were about $130 for a set of three. The line stage only uses one tube, so matching isn't an issue in that application. The Russian 6h23's "bedpan getters" from Upscale Audio are MUCH better sounding and only cost about $75-80 for a set of three if you buy the best low noise ones for the phono stage. Troyca, you have to search vendors to find the old stuff, prices are high in most cases. Brent Jesse (Audiotubes.com) and Tubeworld.com are reliable and expensive (75.00 and up each.) In years past, I combed the Ebay ads and looked for RCA branded tubes that were rebranded Amperexes, Siemens, etc. I think I paid $15.00 for the 60's Siemens, but I was VERY lucky. People are hipper to the RCA thing and they don't slip under the radar too often.
