Some Amish(no elec) use a jackhammer compressor and pump up a 10,000 gallon oil tank buried in the ground. Run air tools all day long. The buried tank won't explode because the dirt helps hold it together. Seems a little involved to get around the no "modern" electricity thing.
If your windmill pumped water, it should be difficult to fab up something to run a SMALL air compressor head. Direct drive it, just be sure to have some relief valves somewhere in the system.
Loud intakes save lives!