I wouldn't think the '73 model wheel pants would even look right on a '59 model. That'd look strange.
They'd be worth buying just for that little $400 cover on the nose pant, then resell them 1 piece at a time on ebay, like most items are. Folks tend to buy one tail light at a time on ebay, because they just need the one they broke when they backed into something, not both. They'll command a higher total price by selling them one piece at a time.
