I dont think I've ever seen a Clint Eastwood movie where he's wearing a poncho that have points on them. I've seen him wearing a serape (the style that Dot's poncho is in) but never a poncho with points on them.
Think the movies he wore the serape in would be the "spaghetti westerns" (cowboy movies, filmed in Italy) that he did... Want to say the titles were "A Fistful of Dollars", "The Good, The Bad, The Ugly"...think there were three of the movies.