One more thought…
We also use the Nunn Finer non slip pad under my husband’s Bob Marshall. It’s fine on his QH and TWH, but I won’t use it on my Arabs, who both have fairly sensitive skin.
The larger size will work with a western or endurance saddle. http://www.nunnfiner.com/Nunn-Finer-Western-No-Slip-Pad-p/71w.htm