Cruppers -Which to buy?

[Sally Aungier <aungish@UNOS.org>]

Well, I've finally gotten the saddle straight, found stirrup leathers with a
low buckle (thanks all for the Webbers recommendations from Ridecamp), now I
need a crupper.  My little mare is continuously changing shape as she moves
from being a life long pasture potato to a lean mean distance horse.  The
last ride in the mountains had me constantly fixing my saddle.  The breast
collar alone was not enough the keep the saddle in place so I'd like to buy
a crupper and would appreciate any recommendations on vendors.
I think that I would prefer leather first and then biothane.  I know that I
do not like the style that hooks to the billets.  I'll be using it with a
Smith Worthington endurance saddle (english style) which has lots of rings
or can accept the tab style crupper.  I am familiar with training the horse
to accept one because I've been driving for years.  

Your suggestions will be appreciated.
Please respond privately

Sally Aungier
Powhatan, VA