Yes! Ball screws can be rebuilt. The majority of the time, when a ball screw fails, it is due to wear, and as such develops excessive backlash and loses preload. In these instances, it is likely the screw can be disassembled, cleaned, any minor repairs performed, and then reloaded back to a preload state without backlash.
Many times a screw fails catastrophically and the ball bearings fall out. Often these screws can be rebuilt as well, assuming there is minimal to no damage to the nut or screw.
Should a screw not be salvageable, LSI can reverse engineer and manufacture a new screw to replace the old one!