You have a museum piece. You should restore it, or sell it to someone that will. I would hate to see it reduced to just a generator, hooked to a Chinese diesel.
Dave's history is a pretty good one. The one clarification is that Hebco was definitely not the first to generate from wind power. Hebco (or the Herbert E Bucklen Corp./ Bucklen himself) is credited as being the first to use an airplane type propeller, instead of the windmill type multiblades (with huge step up gearing), for wind generation. So, it would be the first modern wind turbine versus earlier windmills.
I would try contacting the Elkhart Historical Society and the Elkhart County Museum. They should have old newspaper clippings, advertising flyers,etc. They may have some old-timer that has more knowledge. The Bucklens are an old family in the area. Your interest is in HEB II. His father made a fortune in “patent medicine”.
If you know which airfield that unit came from, searching the local museum and newspaper files might give you more info.
I am not sure what became of HEBCO. They either folded or got sold off in the early 30’s. The depression, completion from Jacobs, and the Rural Electrification Act probably did them in. HEB II founded the Durakool Company (Makers of switches and relays) in 1935.
You might try contacting Wind Turbine Industries. http://www.windturbine.net/
They are the supporters of the old Jacobs units. They may have some knowledge of the HEBCO units. They would also be a good candidate to supply a prop for your machine.