Doc, Hands of Steel (1965)

Doc McGregor, former surgeon become player, is wrongly accused of murder and pursued by Slade, a bounty hunter. In his escape he finds Larry Kitchener's corpse and decides to impersonate him. But his problems get worse as Kitchener was a famous gunslinger hired as sheriff for the people from Baldosas to stop Reyes, a Mexican bandit who has terrorized them.