Groetchen Liberty Trade Stimulator HELP

[GaryLee]

New member here looking for assistance with a restoration: I am guessing that is how most of you found this board? Have just discovered trade stimulators and love the old machines! But my GROETCHEN LIBERTY TRADE STIMULATOR jams after about 5 pulls when a penny will start to jam in the slot on the upper right inside. Have found and sent Bill an email but was hoping someone out there might have an answer? Are there parts / repair manuals available for these machines? Any help appreciated. Gary, Tucson