Colorado RR Museum has some of this kind of shelving set up in one portion of the basement; I understand they obtained it at a good price because the initial buyer of the units canceled prior to delivery.

Some years ago I had a behind the scenes tour at San Diego Historical Society. They had planned for the future and installed the track system for the movable shelving; but had only obtained the shelf units for the material then on hand. These units were being left stationary until more units were obtained as required.