Its basic alu extrusion.
Try this one:MiniTec T-Slotted Aluminum Extrusions. Modular Aluminum Profiles For Custom Construction From Aluminum Extrusions. Custom Clean Rooms, Ergonomic Workstations, Belt Conveyors, and Machine Guards Are But A Few Applications.

Havent dealt with them before and dont have any idea of price but from lloking at it somewhere else in the past in aint cheap.