We get ours done for $45 per ball washer. We break them down ourselves and the guy we take them to will sand blast and powder coat for us. The results are great (the first few I had done have been on the course for about 18 months now and still look good as new). Like Andy's idea of bringing the costs down with my own sand blaster though...
Also, if this is the Ken Siems I think it is, I worked for you at LLGC back in the late 90's....just want to say thanks again for that opportunity, without it I might not be where I am today!