carquest has them for about $50..... part #51000...Napa also has them
it's not hard to change, there are dimples in the door that you drill and open them large enough to get a socket for the bolts to install the new motor. If the motor had not been changed before it will be installed with rivets that you'll need to drill out. If you not sure where the holes need to be the new motor will give you a clue where to look for the dimples in the sheet metal. Only the motor is removed with this method, everything else stays bolted in place