Where can I watch Sitting Bull in United States?

Chief Sitting Bull of the Sioux tribe is forced by the Indian-hating General Custer to react with violence, resulting in the famous Last Stand at Little Bighorn. Parrish, a friend to the Sioux, tries to prevent the bloodshed, but is court- martialed for "collaborating" with the enemy. Sitting Bull, however, manages to intercede with President Grant on Parrish's behalf.