Tube vendors.

Andy is one guy so he can get backed up. But he delivers the goods. Brent Jesse is great too and fast in my experience. But I care about the tube not about the wait. 

Viva's a great little company. I sort of replaced "thetubestore" with these guys as they're nearby (MA) and relatively inexpensive.

I’ve been most impressed by Andy Bouwman at Vintage Tube Services. Very knowledgeable, and really cares about fitting you with the right tube for your equipment. That said.. I also get tubes from RAM tubes… and only from them for my Music Reference amps. I used Upscale Audio many times years ago, and frankly they’re hit or miss… (in my experience). Andy asked a lot of questions about my gear, and what I’m looking for in sound. He has detailed records of all kinds of specific tube gear, and how it sounds with various tubes. Great resource. 

@wolf_garcia … sorry, a tiny bit off topic, but have you tried other tubes in your Freya? If so, which, and from whom (back on topic..)? 

Andy, Kevin Deal and Brent Jesse all know what they are doing. Certainly one of the best is the guy in Wisconsin (Brendan?) and Gregg Levy at High Test in New Jersey for guitar amp (pro) tubes. 

I wouldnt buy from any dealer that says they have a bunch of: "NOS in white box" tubes. Should read "tests as NOS in white boxes".

I won't try to tell you what to buy, audition_audio, but tubes were bulk packed for industrial and military users.  So NOS tubes can come in white boxes.

Krelldreams...from the original Russian tubes I ventured into Sylvania "chrome domes," new Tung Sols, and others I can't remember but stuck with a quartet of NOS GE 6SN7GTBs which have lasted a very long time.

Yes there were, but when you see large quantities of NOS in white boxes that arent JAN or industrial and there is only 1 seller making this claim it should give you pause. True NOS is like being pregnant....you is or you aint. Original boxes dont prove NOS, but they are a very good indication. 

All the above are excellent sources for tubes
Richard Gray , my tech geek swears by Amplified Parts, so thats where i now get my 12 power tubes, 4 sets of trios, Not so easy to match, which AP does their best to fulfill,. RG says they have excellent  testing equipment to match. 
My next set will be EH KT88's. 

Matching is a bit of a shell game. The tubes are seldom run and matched under real world conditions which vary mightily between amplifiers. A match at one point may not at another.

For a well matched set, they should be run for several hours before matching.

Amplified Parts doesn’t have a single mention of matching as related to tubes on their website, so quite possibly are selling sets matched by the original tube vendor.