Gee, these could be used to drive a really big Tesla coil... and I suppose an inverter for a 600 V DC solar array is also a good application, as would be a tig welder. It all depends on how adventuresome you are.
Prices for these found on the web are about US$175, so your pair would set you back about US$350 if something went wrong and replacements were needed. As for simple... for that kind of money I would want a circuit as bulletproof as possible.
Howsabout you find something you think might be suitable for your needs by researching the Web and posting it here for inspection and criticism before actually building anything?
I have lots of "stuff" like that in my "junk box" that I tucked away thinking it would make a cool project... someday. The usual show stopper is the additional parts needed, and their cost, to make something useful. For example, I have one (and only one)
Burroughs magnetic electron-beam switching decade counter electron tube that is suitable for directly driving Nixie display tubes. It counts at rates up to about ten megahertz. These were the cat's meow back in the day (1950s), but are obsolete now. They have a pretty strong magnet surrounding the tube and it is somehow involved with the electron beam switching through the application of crossed-field physics. I don't care to destroy the tube just to salvage a magnet. So now it is a paperweight and perhaps a conversation starter, along with a
4-400B vacuum tube (once popular with radio amateurs building RF linear amplifiers) that my wife sees as a pretty cool thing to display on a bookcase or in a shadow box on the wall.
Perhaps the thread you cited will provide some inspiration, but read the whole thing through. There were some significant gotchas in the original "design". The gate capacitance of your device is huge. It will take a pretty hefty driver to turn those puppies on and off properly.