Kevin's Harps ( http://www.kharps.com/ ) carries that extremely nice harp holder...about $65, as I recall, and worth every penny if you play "rack" harp a lot, as I do.As for my own harps, I use the Hohner Big River Harp (about $13 from Kevin's Harps), as they really sound fine, last just as long as Marine Band and Blues Harps, and I go through 3-4 sets each year (A, C, D, E, G).
If you can't afford the $65, the Lee Oskar holder (very similar to the no-longer available Elton holders most of us started with years ago) is about $15, and is pretty good for the money.