And that is a great holster that he wore later in most his westerns. But his buscadero rig in Rawhide was also an Anderson rig. In a book "The fastest Guns Alive" by Arganbright there tons of pics of actors involved in fast draw. In one Clint is at a fast draw competition and is shown outdrawing Robert Fuller and John Smith of Laramie ( using the holster you mentioned). He also beat Peter Brown who is a great gun twirler. I have on tape a scene of James Garner in Maverick doing a gun twirling routine, while doing dialogue, that is top notch. He could throw the gun over his back and catch it then toss it in the air and make it land in the holster.Go on Hula TV and there's Rifleman episodes there. Look for Star in the Dirt or something like that and see Sammy Davis Jr. do a great gun routine for the kid in the show.
My favorite has to be Steve McQueen in the Magnificent Seven. His speed in that film using a 7 1/2" Colt in an Anderson rig was FAST!