I had a sash on my dress. Actually, the sash was just a really wide ribbon, about four inches wide, and it was wrapped around my waist a couple of times, and tied in a bow. My sash was about $200 but I was given the sash "free" because I purchased my dress from the same designer. What you might be looking for is a wide ribbon by the Mokuba ribbon company. They are pricey, but it might give you a start on a search.
here's a sample of an almost 3 inch sash...not pink...sorry.
http://www.ribbonjar.com/product_p/20322.htm
As far as adding sparkle, you could add a broach to the sash. Just remember, it will be very hard to tie a bow with it if beading is sewn on it.
I hope that helps!