Seeing as how the biggest complaint with CamLocks had been the tiny ID on the coupler X barb fittings, we invested in our own mold at the foundry that is making our new line of cam and groove couplers. The ID is just over 1/2" and 1/2" silicone tubing will stretch right over it as will most tubing if you heat it first. I don't know that the thermoplastic can stretch enough. 316SS and a silicone seal.
Check out our website for comparison pictures: Brewers Hardware camlock type cam and groove couplers