There are two choices Karl..buy the $25-35 repair/rebuild kit from the
manufacture (assuming its US made), or mount an air regulator on the
back of the fan housing, pipe the air pump line to the regulator and
run it off your air compressor.

Are you kidding? There ain't nothin' US made anymore. Bet the US Army even
sources 1/2 its stuff from China. Heaven help us if we ever fight a real
war.

Karl