A few years ago I bought a Van at a Cable company auction for $200, not cause I was really interested in the van but because it had an AC Generator mounted in the back. This unit is about the size of an old tubular style vacuume cleaner and sits behind the seat. it also has a secondary battery with it there and heavy (Jumper cable looking)lines that run up to a heavy duty alternator with a dual battery charging circuit hooked up to it, it only functions when the van is running but I've been able to power lots of stuff off it, specifically all manner of power tools including a table saw, my furnace in my house and some lights 2 years ago when an Ice storm killed my power for 8 days and a small GE air conditioner I bought from Wally-Mart for my travel trailer. (Prob. the same one you have Little white remote $150). Since then I've decided to sell the van and remove the system and build it into a toolbox that I could plug into my truck whenever I need it to power whatever, Including that AC unit in my travel trailer so I can cool it down before we get to a campsite for summer travel, been meaning to try the little microwave in the trailer with it too be nice to have that highway popcorn.
From the looks of it the generator is just a big DC motor tied to a generator head.
Might look around for places that do conversions for utility companies maybe they'll give you a deal, I have no idea what they cost new.
MONGO


Mongo's Garage
Vintage GM Truck's & Parts
https://mongosgarage.com