List Of Small Company Tube Amps

Raven Audio meets and exceeds the OP’s criteria and they are really nice people to do business with.

on the other hand…

Roger High Fidelity is overpriced even at his 50% off eBay prices, and the lifetime “transferable” warranty is a joke. Transferring the warranty requires sending the amp back for recertification which incurs a bench charge, which is fine, until he sells one of his amps to your buyer instead, which he did to me, twice.

Ironically one of those buyers hated the amp and put it up for sale within a few weeks.

The $8500 I spent on the “demo” EHF MK2 was by far, the worst expenditure in my audio journey.

Check out Musical Paradise, esp. if don't want to sell a kidney for an upgrade.

Octave Audio. https://www.octave.de/

Transcendent Sound amp, preamp, eq kits.  All amps are OTL!  Bruce Rozenblitz designs them all and markets them as kits.  Look for his books on tube audio in the bay.

+1 for Aric Audio. I own several of his projects, including his Transcend EL 34 "Push Pull" amp that is simply amazing; it is paired with Aric's Motherlode XL preamp. He is a great guy to deal with, builds exquisite equipment, and will add whatever upgrades you may want. He makes 7 amps of several different topologies, most for around $5,000. Can't recommend his gear high enough