It's just a pcv valve stuck in the end of a hose. Auto parts stores will carry a wide range of sizes, types, and materials. I doubt any of them would be food grade though.
I bought one hoping to use for beer and it smells strong rubber smell - chemical - almost a bit skunk like. I'll not use for beer unless I can find different tuping. it's 5/8 I.D. X 7/8 o.d. food grade hose I found is 5/8 X 3/4 and it's too stiff to use easlly. curls up too much and is a pain to work with. going to just order a long sucker siphon and be done with it. I think I saw the guy on craigtube use one. I'll ask him.
Works great for siphoning gas. For some reason we use them all the time at the hunting camp, no one ever brings gas for the four wheelers. Down here they are lovingly referred to as a Georgia gas card.