If you're in the Minneapolis/St. Paul area, there are two places you could go:
Location: Brooklyn Park
Repairs: Moog, Arp, and Sequential exclusively
He just repaired my Pro-One and I'm more than satisfied with both the price and the quality. His rates are fairly reasonable as well. He's based out of his place in Brooklyn Park, and I highly suggest him if you've got any of the three above makes and don't want to wait for, say, Wine Country to take a couple months to finish a repair on a pot or something.
The Good Guys Audio Repair
Location: 1111 Grand Avenue, St. Paul, MN, 55105
Repairs: Just about everything
These guys are repairing my Jupiter-6 right now. They take a long time and I'm not sure about how much it is or how good the quality of repairs are, but they have certifications plastered all over the walls of the front office. That, and all repairs are warranted for 100 days after it's finished. I'll update this once I get more details.