Surplus Center does not have a loader valve that will work on this tractor because of the orientation of the work ports versus the joystick.What broke exactly on the current loader valve? Those usually don't break often, if anything it's parts of joystick linkage that ends up breaking.
Also, is it cable operated via a joystick on the fender or the joystick is mounted directly on the valve? If it's the last one, then Surplus Center has a couple good valves for sale around $150 if I recall correctly. Will work just fine.