There really isn't a whole lot inside an electric motor to go wrong, so chances are it might be a simple fix. Unless something really bad happened, like the winding melted or a bearing sheared off, it should be repairable.
If you know anyone in oilfield maintenance, ask them where they send their motors. Oilfields go through lots of electric motors, so they should definatelly know where to get them fixed. You can also look in the phonebook under electrical repair or industrial repair.