Which engines can I put into a Toro ZMASTER Z252L 62" Commercial Zero Turn Mower Model #74212? Is there only the one? I know it had a 26hp liquid cooled kawasaki, but I'm wondering if others can be put into it and which? Also, where would a find a good used one? ARe there sights with used ones that are reliable...? I can't find any on ebay yet.