I knew from the pictures when I bought my van it had no spare, and knowing it had very old tires I wanted to have one with me so I went out to see what I could find at the local yard. All I could find at that time with 5x5 wheels and decent tires was a '95 Caprice. So I took one with a big Winterforce tire.
It occurs to me these would make a super low buck custom wheel choice as they're plain, smooth steel wheels. Add a trim ring and a spider cap (or even mount up some Rally Wheel caps) and you'd have something different. It's not too hard to find vintage 15 inch trim rings at swaps for cheap.
Just painting rallys black looks pretty sharp too.