[Alan Brinton]

Well, I would visit a Ferrimart or other hardware store and look at plumbing supplies and at tubing. You may be able to find a kind of hard or semi-hard plastic or rubber tubing that fits snugly into the mouthpiece receptacle o or a plastic fitting for plastic tubing that does. That would be your foundation to make the connection. Then you can increase or decrease the size of the other end of a short piece by getting tubing that fits snugly over or inside that. I have used rubber tubing to extend a mouth piece. The kind of tubing that I have folds too easily to be used as your melodica hose. I have also used surgical latex tubing, which can be stretched to fit a fitting or tubing that is significantly larger. This kind of latex tubing is also used by scuba and diving shops. It can also be used as a longer melodica tube, although there is sometimes a problem with folding or with moisture collecting in it. Anyway, I think it is possible to rig something.