eBay

Like new Brunson 231 Series heavy duty stand with a working height of 28" to 42". 

This stands may be used to support all types of metrology instrumentation, from portable CMM arms to laser trackers and scanners, to laser alignment devices, particularly when working with surface plates, machine tables, way checking, and assembly operations. Stability is the keyword here; this stand maintains instrument position very well, but it is not the type of stand that you throw over your shoulder and carry around! Mobility around the shop floor is permitted using the drop-down casters under the heavy-duty tribrach base which are engaged and released by a foot pedal. An air-check mechanism provides backup protection to prevent sudden drops of the instrument column in case the operator simultaneously releases the collar lock and main handle while disengaging the ratchet pawl.

http://www.brunsonkc.com/LEN/pdf/231.pdf