Wanted - used commercial sewing machine with walking foot

Needed - a used commercial sewing machine in good condition with a walking foot that would be used for repairing horse blankets. The machine must be able to sew thru synthetic types of leather as well as nylon strapping. The average thickness of a horse blanket could be up to 1/2 inch in thickness so the presser foot must be raised high enough to allow the material to pass under it.