You can watch it online at this link. (not any more the video has been blocked.)
Emanuel Levy says,
The lack of a distinct Indian perspective may be the reason why this work cannot be taken either as the final statement on what Ford thinks of Indians or as an apology for his former movies. Even so, for a movie made in l964, the attitude toward Native Americans is more liberal than other Hollywood movies of the time.
DVD Talk quotes another reviewer as saying, " Ford could sympathize with the Indians but wasn't capable of presenting them as anything more than stiff symbols". NativeAmerican.co.uk has a review. TCM has information.