hey-Hey!!!,
I think I won't regulate. Choke input above critical current will be fine I think. I'll also need a smaller bi-polar supply for the MC-stage's OP amp. Two chassis with power on one and signal on the other. DC heaters amounting to about an amp and a half of 6.3 will be needed. Again, LC filter with good diodes. For B+, a pair of damper diodes should make a dent in the overkill quota...:)I will start with something quite like the Bottlehead seduction, but with a relaxed PS instead of run to 99% of redline, and tubes chosen for something other than minimum filament draw.
cheers,
Douglas