if you want the plastic liner between the leaves, search for "leaf spring liner" with google, you will find many options.
i did a bit of internet research on the front springs in the parts wiki because mine are all busted open at the rear eye.
The front spring pack is the same part number for the 1 and 1.5 Ton,
1941-50 7 leaf assembly part# 3656425
1951-53 7 leaf, assembly part# 3694885
then for replacement purposes a 9 leaf assembly pops up, but this may have also been the spring if you got the heavy duty hauling options with the rear auxiliary springs?
1947-50 9 leaves, assembly part# 3657834
but it gets more fun, the individual leaves in the assembly each have their own part numbers.
the top leaf is part number 3656426, no thickness specification in the parts book that i could find
size 2 x 40 inches (eye center to center)
axle location from ends: 20-3/8 - 19-5/8 inches
this leaf is no longer stocked as a regular produced spring from the places i called in Canada.
however i was quoted 185 CAD (about 140 USD) to have it custom made.
which means you could ask for any thickness or thinness you want when ordering the custom one.
and then you can mix and match all the remaining shorter leaves under it until you get the softness you desire.
fun fact, if you are like me and want to crawl under all the trucks at the junk yard looking for this leaf before having a new one made.
that top leaf is also used in the following spring assemblies
3656425 7 leaf 41-50 1 and 1.5 Ton
3657834 9 leaf 41-50 1 Ton and 51-53 utility with H.D.
3697686 8 leaf 51-55 1 and 1.5 Ton
3695108 11 leaf
3703307 9 leaf 51-55 1 and 1.5 Ton
3711113 9 leaf 54-55 double wrap eye
3665355 8 leaf 48-50 D-D
3691884 11 leaf 50 TR TS
3694885 7 leaf 51-52 1 and 1.5 Ton
best of luck hunting
-stan
