what you can do...not sure if recommend it but i have wanted to do it; i have seen other mechanics do it. very carefully drill a hole in the bottom of the ball joint for a grease fitting, install a grease fitting, remove the old boot. pump a load of grease through the joint to get any dust out that may have gotten in there and put a new boot on it. keep an eye on them every 6 months so you can catch them before they go bad. good luck.

Terry