None there is 1 with a charmeleon and the last of the elite four has a charizard

You get rhyhorn in victory road and evolve it at lvl 42 you can catch them at around 36 so getting there wont be hard

You get it in the game corner for goldenrod city

You bump into the guy in cerulean city you chase him and eventually battle him after you beat him he tells you were he hid it.He hid it inside cerulean gym behind some tubes