What should I do with this crippled Schwinn? (Busted rear wheel)

I went to meet this guy the other day to buy bike for my daily commute when I noticed he had an old Schwinn Super Sport in the corner. It was a light steel frame, whole bike weighed about 23 pounds or so with all Suntour parts, but it had a busted rear wheel. After a bit of talking I took it home for $85 with the busted rim: he called a shop for me down in Seattle and said I could pick up a used rear wheel for $15 there, so it seemed all right.

Well, turns out today that the shop didn't have any $15 wheels (I should have known). They had one for $50, but I was hesitant.. total would come out to $60 w/ installation including swapping out the good 6-speed freewheel cluster from the busted wheel.

What should I do?
1. Go ahead and buy a new rear wheel, have them install the 6-speed cluster
2. Look for used wheels on Craigslist (can I use a wheel with a shimano cassette? do i have to get 6-speed?)
3. See if the guy will take it back (last resort), I'm not sure how much a Super Sport is worth, though, and whether or not I got a good deal. But after all, he put me under the impression that I could have the bike up and running with $15.

I'd love some help.

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2005 Bianchi Brava

I would replace the wheel, especially if the quality of the new wheel was decent (i.e. new or almost new)

You may end up spending more than you should have overall, but it is a bike I think would be a good commuter for you.

I don't know the specific year/bike to know which rims it comes with... but if it has chrome rims, and you need to replace them, you should replace them with aluminum, especially in the Pacific Northwest due to better braking in the rain.

There are several places you might be able to pick up a used rear wheel cheap in Seattle

Recycled Cycles- www.recycledcycles.com
Second Ascent- www.secondascent.com
Bike Works- www.bikeworks.org

of all of them Bike Works might be the most likely to have the vintage that you are looking for and its run for a good cause.

If that old bike is otherwise in good condition, it is probably worth getting back on the road. If it is friction shifting, you are not restricted to 6-speed and could go 5-7s, depending on rear hub spacing. Again with friction, you can use any brand freewheel or cassette. Unfortunately, Suntour indexing doesn't work well with anything other than a Suntour freewheel. If you are looking to stay low budget, you should be able to find a used wheel that will work.

I live in Seattle and sent you a private email about an old pair of 27" perfectly functional, thread-on freewheel wheels that I have that I could sell you for a good price. I considered eBaying them but the shipping would be more than they are probably worth.. Your mentioning Craigslist gives me a good idea if you don't want them.