Hah! No "expensive" NOS? "Late breakup"? In what amp? Try a JAN / Sylvania or JAN / GE 5751. You get "late breakup" and it will outlast any "GT, EHX, JJ, etc." You may only need to buy one. It will effectively last forever. I got a MST of 'em from an ex- Air force avionics technician. The only reason "reissue" 12AX7s are "crazy gainy" is they're crazy inconsistent.