Need help. The plastic pulley that came with my Paxton 1220 has ridges (looks like where the pulley was put together form 2 pieces) and is real scuffed on either side of the ridges. I suspect belt bounce and slippage. Anyone got a number of a steel or aluminum replacement pulley? The stock pulley is dual bearing, 78mm od, 33mm wide, and 17mm hole for the bolt. Thanks for any help.