I can only echo what Robin says: try and get them repaired under warranty. Although I not that some sellers of replicas that have diamond cut finishes only give a very limited warranty on the finish.
I used Pristine to do a set of genuine ones a few years ago. They did a good job of it for reasonable money, but their prices may have gone up a bit since then.
Personally I'd just get 'em powdercoated either anthracite or satin black.