Out of like a two liter or any plastic? Its not like its expensive. And they're fun to make. Just make another. You not even supposed to refill plastic bottles. They're meant for one time use to drink from then toss them. Horrible horrible inventions.
Well replacing the bottle is all up to you man. If its all nasty, dirty, and smelly then yeah id say replace the bottle, but if its still somewhat clean then keep tokin the mofo!