repairing a voltage regulator = Cub 154 Lo-Boy

I finally got enough rewired and jumped out to point me to my "new looking but not new working" voltage regulator. As you can see, a little water got under the cover seal and cooked the wire leading from the BAT terminal to the magnet assembly. I've found a good used replacement but no one wants to bother repairing this one because of the chance it won't work when they are done. There is nothing wrong visually with it except the wire needs replacing. New ones are $70+ and there's so little apparently wrong with this, I hate to throw it away. I'm tempted to clean up the "points" with a point file and rewire it as a spare, has anyone else tried this?

thanks!