[LAU] (For the crafters)Swtich to choose one from four reed/pipes

This is a bit offtopic, But maybe one of you has an idea how this could be done: I'm searching for a way to build a (part) of an instrument which consists of four pipes with reeds in them (like a clarient or oboe, only with just one tone) That means: if you blow in just one of them you will hear a sound. So basically its not one but four instruments bound togehter. Each of the pipes is only 7mm bore/diameter so the four of them will fit togehter in one hand. The material is copper or pvc, still experimenting. The air will be filled in with some kind of mechanic and for all four toghether. The question now is: How can I only let one of the pipes sound? Its not needed that more than one sounds at once. But it IS needed to switch quickly (up to one second) between them and it should be possible with just one hand. After switching the state should be consistent, which means you can use your hand for other things then. Any Ideas? The nicest way would be to do it with some existing parts which can be bought, maybe for tubes or ducts. greetings, Nils