Thanks all, that was very helpful. I can eliminate two candidate tubes straight off the bat - the Shuguang 845C and KR 845 are off the list because of incompatibility.
Someone mentioned the Sophia Electric 845. A quick google shows this: http://www.sophiaelectric.com/pages/se/845.htm
Is the Sophia 845 a rebranded tube, or do they manufacture it themselves?
Brf, would a quad of SuperTNT Nobleman be as expensive as the other tubes (RCA, Amperex, etc).
Someone mentioned the Sophia Electric 845. A quick google shows this: http://www.sophiaelectric.com/pages/se/845.htm
Is the Sophia 845 a rebranded tube, or do they manufacture it themselves?
Brf, would a quad of SuperTNT Nobleman be as expensive as the other tubes (RCA, Amperex, etc).