I am selling a few single tubes from 6SN7 family. Two of them are all technically identical to 6SN7 after using adaptors. All tubes are measured super strong close to NOS, balanced, noise and microphonics free. These tubes are all from 1940s, very expensive and hard to find in good shape nowadays. After a few years continuous searching, I finally gave up paring them up. Schiit Lyr, Vali, Bottlehead Crack, Darkvoice, Xduoo TA-26s rollers don't miss these

Tube 1: Tung-Sol 6SN7 Black Glass, Round Plate, Round Mica. The round mica is considered rarer than the oval one. I haven't seen any of these pop up on ebay for very long time. The base has a crack, but the tube is firm and performance not affected at all. $150
Tube 2: Tung-Sol (KenRad rebranded) 6SN7GT Black Glass, Oval Mica. $150
Tube 3: Tung-Sol 6F8G/VT-99 Black Glass, Round Mica. The tube has very low hours. It's probably not broken in yet. $150 adapter included
Tube 4: GE 7N7 vacuum tube - tall bottle - 7N7 tube made by Sylvania. Regular 7N7 tubes are easy to find today, but not these tall bottle version. These are considered better sound comparing to the shorter ones. $75 adaptor included

$425 to buy them all. PayPal fee included. I can ship to anywhere, but cost depends on where you are located. If any questions, feel free to pm me.