Two Guns for Two Twins(1966)

Original title: Dos pistolas gemelas

Sally and Jennie are twin sisters who travel the American West with his uncle Nathan who makes his living as a tooth-puller and also sells a cure-all elixir. They travel by wagon and attract the audience with their dances and displays of marksmanship. Unexpectedly and before he dies, the old man manages to gain ownership of a ranch in a poker game. Now, the two girls are the new owners but the land is coveted by several people in town.