I think they can be had "new" for about $125 from various sources. If you have all the pieces and more time than money, you could probably get the parts you need from a generator / alternator shop and fix it yourself.
If it is in that many pieces, you may want to go with "new"...an alternator / generator shop might be more, but you never know.
You could probably get one out of a salvage yard in good shape for 1/2 to 1/3 of the "new" one. Good luck...BB