small fan looking internal part that meshes with the screw chicago pnuematic tow behind

by kevin
(cmch nj)

hi i need parts for a chicago pnuematic tow behide 185dz i think they call the part the stars it is a single screw diesel power 4 cyl nissan any help on where to buy parts for this unit would b greatly appricieated thank you kevin kevint214@comcast.net