Don't forget Missoni! They ALWAYS have great scarves and they never go out of style. I LOVE mine!
Also, don't rule out scarves made in Japan for silk ones. Japan has a very long and prestigious silk making tradition and hands-down some of my favorite silks are Japanese. I actually have a whole collection of antique Japanese silks and really, it is some amazing stuff!
Don't forget about vintage scarves. Stuff like vintage Givenchy, Vera, Echo and the like--they were great innovators in textile designs and are making a real come back now.