If you still cannot find one. Try making your own , details on my tips files below. Find a scooter/motor bike inner tube right sort of diameter , cut a strip, cut across the width to make thinner . Maybe cut from a flat sheet of .5 or
1mm rubber. The set in the "cylinder" probably no matter for a record deck, smaller one for cassette deck requires offsetting angle of the ballister pulley drive.-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on