Support Your Local Sheriff! (movie, 1969)

A quick-witted drifter wanders into a lawless town in the midst of a gold rush. Shocked by the prices of food and meals he reluctantly takes the job of sheriff by amazing the Mayor with his lightning quick, dead eye pistol accuracy. He makes the town council know that he is really just passing through on his way to Australia and he will pull up and leave anytime he chooses (including at the first sign of real trouble). His first day on the job he takes on the biggest, meanest ranching family and meets his klutzy love interest.