Finally getting an early A-Body
there may be a local spring shop in your area, and if so they may have leaf springs on the shelf,, i know in my area there is a shop that has stuff like that still on the shelf,,
ide replace them even if only with stock rated leafs,,my gues they may be sagging a little by now and if not in the budget take them apart one side at a time,sand or sand blast and get a good chassis or rust olem paint and paint um up,,,,
scribe a mark in each so you know which one went where for reassembly,,