Here is a refined version of the B-17 circuit, including power supply. The transformer used in the supply is one that I scavenged from an old vacuum tube pH meter. The supply is a voltage doubler type and includes a dropping resistor to get to the required 390 volts. Likewise the filament circuit requires a dropping resistor since there is one less tube than there was in the pH meter. Here is the circuit.
Next step is to build the bill of materials and order the parts. Stay tuned!