You should probably be able to go to any local jeweler. Many of them carry this setting in stock, or can easily order it for you. When I ordered mine, the setting was available in white gold with white gold prongs or platinum prongs, yellow gold with either white gold or platinum prongs, and all platinum. Mine is white gold with Plat. prongs. It is a very pretty setting, and looks equally nice with a plain wedding band or a diamond band.
Here is my all-time favorite tulip-like setting. If I had a round, this would be IT only in all platinum or a yellow shank with white tulips. Drool!!!!!