Well, they are 3/8 tubes, so any bushings for similar tube sizes (Caraba/Atlas/Patriot, Classic American Rollerballs, etc) will hold the tubes on. I don't have any of the kits to measure the parts, so I cant say how close any of these kits may be, but you could always use them and a set of calipers (assuming that the bushings are smaller, it would be pretty hard to turn to significantly smaller than a set of bushings...) or if you have the live and dead centers, just turn between them with just the calipers...