The design I use allows the hatbands to be adjustable, to a certain extent, which is nice if you're buying for someone else and may not know exactly what size their hat is. The cost is $53ppd.
As always, I can use your horse's hair (but beware, it needs to be LONG!), or I can use stock hair. The length of hair I usually need for these is at least 27".
Here are a couple that I made up as Christmas gifts:
All of my jewelry can be seen in my Photobucket album: Horsehair jewelry and keychains Photos by sharonl_02 | Photobucket PM me for details, or if you're interested in having something made.