Is this a rub spot? Kinda makes the spring thinner. Or a short more like a cut point? Springs are hardened. I would think that the thinning would make it weak and a short wear spot would be dangerous. Might fail completely. I would look at replacing them. You might consider taking them apart and replacing the worn leafs. And you might consider a replacement set. Compare the costs in time and dollars to help decide. Do you have a "spring" shop nearby? Ask the 4x4 rock crawler folks they will know. That might get you on the road with not too much money and time. Let us know how you go and what you decided.

Steve H