MZ61 Deck kit 

some kits us cast iron spindles these spindles with work in place of both

(QTY 3) Deck Spindle

Direct Replacement for OEM Part Number(s): 539112170

(QTY 3) Idler Pulley

Direct Replacement for OEM Part Number(s): 589766102, 589766101, 581813701, 539132728, 539131148, 539112196, 532132728

(QTY 3) Gator Mulching Blade 96-900

Direct Replacement for OEM Part Number(s): 594893101, 594892701, 539110460, 532424752, 532422719, 5321397-75, 532139775, 532134149, 531307223, 531005085, 424752, 422719, 24676, 24652, 139775, 134149

(QTY 1) Deck Belt

Direct Replacement for OEM Part Number(s): 539104335, 522795901