Storing carburetors can be challenging, the linkages make it so they don't sit flat on a shelf, the fuel lines can do the same, and resting the carbs on the linkages could lead to them getting damaged. Carb stands work great, but at $30 or more they can get pricey for just storing carbs....why not use that 3D printer collecting dust on your desk to print your own?
 
NOTE: The threaded hole will need to be tapped with an M8-20 tap to clean up the threads so the printed bolt will thread in properly