Those old JC's are about as bulletproof as it gets for am 1800rpm air cooled machine. Still tons of them out there as reefer backup in the attics of older grocery stores and telecom sites all over the country.
If you're looking for setting it up as standby, you'll need to get a load calc and figure whether you're able to run on city gas or what size propane tank you'll need for your what you want for run time. Also had some customers that set them up on a roll cart with some outlets and daisy chain some bottles together, but that's a big hassle to drag out and set up in the dead of winter.
I see it's local to the panhandle, so if you do pick it up you may want to give Bob at Selkirk Power Gen in Ponderay a call. He's a character and will talk your ear off, but knows his stuff.