Hard to find 10” drum brake springs

This when you really need the parts store with the old books and the guy that's been around so long he knows half the stuff by heart.

You may have to look in the Chrysler Parts Book. Get the p/n for adjuster spring your brakes. Then look to see if its the same for front and rear, 9", and 11" Then check some other years.
With the OEM part numbers, you may have chance of finding a cross reference or at least know what other models and brakes it was used on.
A lot of brake info didn't get transfered to the later books, never mind the computer for companies like Wagner Raybestos etc.