McVeigh Truck Springs in Michigan, has NEW '59-'60 Tbird (and others) rear leaf springs. They have bushings and other parts also. They are made in the USofA. Here is their main website, followed by their eBay store website. Contact Tom McVeigh (989) 826-3682

http://www.mcveighstrucksprings.com/

As of this date, their main website is down, and they were not aware that it was until I told them. They gave me the correct link to their eBay store, which is operational. Here that is. https://www.ebay.com/str/mcveighstrucksprings