An old photo of several hundred bucks worth of good ceramic door-knob caps. rated at 30kv. Conveniently over voltage just results in a jump between buss-bars instead of blowing up a $14 cap.

This actually adds up to about twice what is needed for my current power supply, I blew up my other 15Kv supply and am stuck at 30ma current. Oh well, someday I'll have time and money to upgrade.