That depends on what you call cheap?
You should be able to get something secondhand at your local gunsmiths, you are meaning an air rifle? With air rifles, in my experience you are better off with a poor condition good quality one than a new crappy one. One I had many years ago was a BSA airsporter, underlever with a 40mm scope, quite accurate and I guess now you could pick it up for peanuts, something like that would do you.