If you're to the point of quasi AC you could look into building a cockroft walton multiplier. The are very easy to construct.
Use an input resistor to limit current into multiplier, and use and output resistor to limit current draw from the multiplier, otherwise you smoke the diodes. They can be powered from 120Volts, but it is too dangerous if you are not experienced with it.
I've built this type of circuit to charge capacitors for laser flashlamp power supplies and they work great.
Check
Jochen's High Voltage Page for details on this kind of circuit(look under the high voltage section under
mutilpliers) to get the voltage you need you'd only need a 2 or 3 stage multiplier as opposed to the 100,000 volt units he shows.
You could even power it off 12 volts with a low frequency DC inverter driving the multiplier.
The transformer method would work as well although they will not be tuned well for your circuit, CW multipliers are a solid state solution to the same problem.
And when in doubt, just modify the flash circuit out of a disposable camera to do what you need. There is information on these.. Schematics of a Kodak disposable camera **broken link removed**