They come as a pair along with the threaded rod and kit that runs through the axle. I would have ordered the eco-sliders that have black Delrin (made by DuPont) plastic. Not too difficult to fabricate, either. The Delrin can be had in different diameter rods - I ordered a 2' length online, cut them, drilled them out and ran a 5/16" stainless steel threaded rod through. Used a bit of 3/8" int. dia. tubing to buffer between the rod and the axle, and nylock nuts, countersunk below the outer face of the delrin.
Mine are more "rustic" than the eco-sliders, but less rustic than scrapes along the swingarm would be.
