Rooze, I purchased my Amperex 7308s from Tubeworld (www.tubeworld.com). They were expensive ($750 for a matched set of 4 NOS Amperex white label from the early 1960s) but well worth the cose. I reseached info about tubes - the best source I found was "Joe's Tube Lore" the link to "Joe's Tube Lore" can be found in the thread "Amperex PQ6922 vs Amperex PQ7308" near your thread here on Audiogon. You can also e-mail him (he responded in that thread) to see where he purchases tubes - might be different from Tubeworld.
I also have to agree with Jafox as I have heard nothing but good things about the LS5 mark III.
I also have to agree with Jafox as I have heard nothing but good things about the LS5 mark III.