I have a few old cars, one of my favorites is a 1955 Buick Century. This story is actually about a friends 1955 Chevrolet. About 20 years ago. We were out Cruisin' one summer day and around 10 miles to the next town he threw a fan belt. Naturally he had no spare. I remembered a trick I learned years earlier.
My wife had some panty hose. I cut one of the legs off, pulled it tight around the pulleys and tied a tight knot. Makes for an improvised belt. It worked well enough to limp into the next town where we were able to find a replacement.
I realize women now days don't wear nylons or panty hose much anymore so may not be all that helpful.