I have a 1972 Super Sport that I restored to 10 speed riding order. My BB was fine, and I haven't had any troubles with the one piece crank. If your BB is really making a fuss, I'd just overhaul it. You can get a decent rear wheel for $100, and Harris (Sheldon's store, more or less) even has some prebuilt 27" fixed wheels. Personally, I'd have a 27" rear built by your LBS so you don't have to worry about a front one. The stock SS rims are alloy, so you won't run into that problem. I'm actually looking into rebuilding my original front wheel, and the rim and hub were still in good shape, I just had some stripped spokes. Those stock hubs are quite nice, I believe they're Normandy.

Hope that can help, feel free to PM if you need some details (I'm not saying I'll have all the answers, though ).