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If you have a 6.3V and a 12.6V filament transformer laying around (wall wart supplies can be parted out if ya want), some 1n4007s, spare filter caps, a couple of LM317s (or whatever that adjustable regulator radio shack stocks is), and a decent assortment of resistors you can build a cheap supply for that set. Connect the 6V xfmr primary to the power plug, connect the 12V winding of the 12V xfmr to the 6V winding of the other full wave rectify + filter the primary of the 12V xfmr (which should give ya about 85V) regulate that down to 67V DC with a regulator CKT. Now fullwave rectify and filter the junction of the two low volt windings, and build another regulator circuit for the filament voltage.
Cheap and simple (also a fun exercise in power supply design).
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