it probably just needs some new brushes. They are normally not that hard to get to behind where the wires go into the motor. Since it is already broken see if there is some way that the plastic plug that goes into the motor has a way of being worked out(looks like possibly a retaining clip on top?). If so you will probably find a small spring attached to a little piece of metal that is partially round on one side and that is the brush that needs to be replaced.