Bush Hog TDM-17 - need gearbox, prefer used

I had the gearbox on my TDM-17 Bush Hog (tri-deck) self-destruct due to a mower accidentally lifting up. Pretty much every part is torn up other than maybe the casting. Looking for a used gearbox, but I'm not sure where to look. Anyone have any ideas? Will a gearbox from another unit fit? 

 GENE HEY THIS IS KORY HERE AT MESSICKS I TAKE CARE OF ALL THE BUSH HOG ORDERS AND FOR U I DID SOME RESEARCH AND FOUND THAT A NEW GEARBOX IS ONLY 257.65 AND THEN SHIPPING ALSO SO YOU COULD WALK AWAY UNDER 300.00 DOLLARS AND TO BUY A USED ONE YOU NEVER CAN TELL HOW WORE THE GEARBOX IS THANKS GENE YOU CAN CONTACT ME AT KORYF@MESSICKS.COM