We had a 1480 that had one made by Rodono Industries out of Canada. It was hydraulic drive, and we really liked it, however I have no idea what they cost. I found this with a google search: Rodono Industries ltd. Replacement Straw Chopper Rotors, Stationary Knife Kits and Feederhouse Reverser RR n1 Clive AB T0C 0Y0 Ph: (403) 784-3864 ~ Fax: (403) 784-2402