The class is gas welding. I assume argon but it doesn't matter. I'm not interested in pursuing anything that will require gas supplies. The class includes oxyacetylene torching. I won't be doing that either for the same reason. I want something that I can use forever with supplies that I can accumulate and store myself. I can't store gas.

I've always heard "gas welding" used to mean good old oxygen-acetylene welding. The class including torching -- which I asssume means cutting -- would seem to support that. Where you use argon (and a device with the electrode fed through the handle from a spool, right?) is what I've always heard called "MIG welding".

Oxygen and acetylene tubes are incredibly durable; you can store them (with no or only minimal shelter from the weather) for years, probably decades. (I know this because we used to.) And you could of course store lots of them; just pile them up somewhere. Certainly more than you could of the high-voltage electricity you need for TIG or MIG welding...