One word “ TELEFUNKEN “! I have NOS 12AU7’s ( E82CC, ECC82) in Telefunken , Tesla, Seimens , Mullard , RCA, Tungsram . They all are better than new stuff . They have distinct tonal differences . I use 5 different NOS rectifier tubes which raise or lower the voltage and effect my power tubes . So driver and rectifier tubes are all NOS. They last a long time . Power tubes - I have NOS GEC KT88 and KT66 , NOS Tungsol 6550 ( 3 hole ) , and SED Winged C 6550 and 6L6GC. They are better than current production tubes and more expensive. New production, I have Gold Lion KT88 and KT77 ( very nice sound ), Psvane TI KT88, Tungsol KT120, JJ KT77. Of the new stuff I am fond of the GL tubes . But for your application Telefunken NOS. FYI Brent Jesse’s site gives a very accurate description of SOUND from various tubes . FWIW, I have $3k in tubes for a $1500. Amp , so you see where this can take you 😝. Shoot me a message if you have specific questions . Happy Listening , Mike B.