Used to be a dealer for St. John Welding. Still have 1 set of MF 510/550 cylinder bars and rethresher bars with rethresher channels,,Rethresher bars come with bolts...Have had these bars for a while,,,always in shed, but have some sheet rust in spots, still new condition. Cyl bar oem no. is 294144m91 and 294145m91,,,have 7/16" hole in them---these ARE NOT for the high inertia 550 cylinder. these are new, not rebuilt. List for whole package is usually $400-450..., will sell these for $100.00,,,get that combine ready,