Respace the rear and run it. Use ATF, I do on my three speed Racer and it runs super smooth. You'll be fine. Really, what's the worst that can happen? Wreck it? It would get me thru this storm we are having, so I'd let her rip. I just got back from the grocery store on my Miyata SS, and from my experience, I'd worry more about tires than that hub. As for the coaster brake idea, I have not tried that. I just use cantilevers with Kool-Stops year round. I don't go fast enough to create stopping issues, especially in eight inches of new snow.
St. Paul, Minnesota is home of the "historic" 2009 Christmas storm.
Oh, a Surly spacer kit works great as well.