I really, REALLY wish my digital camera wasn't out for repair right now, or I'd post a pic. The hub I used is a Schwinn anniversary (which would be 1995) chrome steel coaster hub that was used on the cruisers. The spacing is different (what is the spacing on an 80's road bike? I know nothing about spacing), but works with axle spacers, and a spacer on the bolt that holds the brake arm to the frame. It's ugly as heck, but works super so far. I only payed $10 for the hub, too, so I couldn't go wrong. It's actually become my favorite bike by far. Short of getting tubeless tires for it, I can't imagine how it could become any less trouble free.

Shecky- I'm probably going to put a front brake on mine, too. It makes more sense to wear out brake pads instead of a hub sometimes.

Good luck with the mountain bike!