Minor rust pitts kill springs ,that said mopar used a very tacky enamel base each part was dipped then assembled .on my oem cars or loosely put a matching #s car would have the springs re arched you can do this yourself then use a plastic tub filled with one gallon of rustoleum or like kind .Then slide the springs through the tub and let drip dry .Also look at the new mopar springs good reference, most guys never think about the spring #s as part of a matching car .i like the cast blast finish by semans found at many engine rebuilders supply.good luck
Same here with me, the cast blast finish is my favorite too.
As for re-arching, I have had 3 sets of original leaf springs re-arched by the same spring shop over the years on 3 different cars. The first was my '69 Satellite over 20 years ago, & still in excellent shape. The second, was my wife's '75 Duster that she drove over another 100,000 miles on the re-arched springs before we sold the car. The 3rd set on my '71 Scamp, only lasted 2 years before they sagged back to where they were before I had them re-arched.
I had a custom set of springs made to replace them by a local shop that are now about 15 years old & still great, except they look awful from surface rust & scale. There are six leaves on each side & each one is thicker than stock. I asked the guy who made these why the other re-arched sets lasted & not this set. He said it could have been that they were subjected to different condtions over the years, or as simple as the original metal composition just not as good as the others.
I forget what I paid to have them re-arched, but it was substantially less than new ones. Anyway, here is what the cast blast finish by Seymour looks like.....
One side almost done after disassembly, wire wheel stripping, & painting. The toughest part about the cast blast finish is not being able to tell where the bare metal ends & the paint is while spraying.
One last crusty leaf with 5 finished ones before the rear swap: