My springs look the same way on my '96 (last of the Gen II body style), and have looked that way for over 7 years that I have owned it. They look even worse when you start hammering on it. I have 125k on the clock, I am pretty well convinced they have had it as well as the front springs.

As best I can tell, finding rear springs will basically be from a spring shop, and I am sure a couple of mail order places---I just haven't really looked into it yet.

BTW, if its a Dakota short bed, Definatly make sure you have a weight distributing hitch and sway control--actually good to have no matter what. These trucks (even long bed or extended cab for the extra length) are border line in my opinion for towing anything but a 2000 lb car and trailer. And yea, I have towed much more than that in the past I hate to admit.