This low poly model is one of the 60+ 3d assets included in the LightArchitect pre-visualization add-on for Blender 3d. It is based on the Dana Dolly, a slider used in the moving picture industry. Also included in this download are low poly models of the Arri Alexa and Red Epic cameras.
Note that this 3d model is only the camera. To get the full film pre-visualization add-on use this link: https://www.blendermarket.com/products/lightarchitect---filmmaking-add-on