Good grief, you can't figure out how to buy a radiator for a 1991 2.8 ( Not a 2.6). Try clicking the FastLane button at the top of the page. They are about $250 to $300 or so. Available from about a zillion sources, including Autozone or MacParts.

I would get rid of the car quick, as there will many more complicated and expensive problems to deal with.

Steve