You could buy a B1-C1 carb kit with w/ everything from air filter to new throttle cable & and carb and manifold. A 19mm Dell PHBG rep/copy carb for around $60, going to need a jet kit w/ a 1.01mm jet and a few more down. My avatar 50cc C1 Camel Honda has one, takes some fooling around to get it right. You might wants some carbon fiber reeds also.