Tube Dealers 2021

Another vote for Brent Jesse. I  need an upgrade to vintage tubes for my Jolida phono stage and he was  extremely helpful and made an excellent recommendation, a 1960's matched pair of Telefunkins, and I then also pulled the trigger on upgrading my Jolida Black Ice box and my Rogue Sphinx V3 as well. I obviously wanted to  go with vintage  tubes across the board.

Audiotubes.com Brent Jesse

Vintagetubeservices.com Andy Bowman

I have had good dealing with:

http://www.triodeelectronics.com/tubes.html (Ned)
https://tubeworldexpress.com (Brenden Biever)

You may also want to try:
https://www.tubesandmore.com 
https://vacuumtubesinc.com
https://www.nosvacuumtubes.net
https://www.jacmusic.com (European)

seta45

Brent Jessee Recording is my go-to, for rare, NOS, 6SN7 Octals.    I've gotten some of my very best NOS, nine-pin miniatures (especially, my Siemens), from this seller, in Germany:   https://www.ebay.com/usr/audiotubes_de?_trksid=p2053788.m1543.l2754          I've never been disappointed by either TC Tubes, or Upscale Audio, when it comes to NOS or new production power tubes (6550, KT88, EL34, etc).        https://tctubes.com/          TC Tubes surprised me, when one of an octet of GE 6550s went bad, after almost two full years of service.   I returned the set to them and they ID'd the offender, found one that matched the remainders and gave it to me, gratis.     Hard to beat that kind of customer service.

I'm not a heavy tube user, but found Ken Chait to be helpful.

https://www.tubeman.com/index.php?l=page_view&p=contact_us