Looking for a velcro bookbag holster that uses 1.5 inches straps

So I recently bought a red rock outdoor recon sling ccw backpack http://ift.tt/28NIQcq . I don't carry off the body very often but I use it so I can carry my full size m&p comfortably. My problem is the included velcro "holster" hey give you uses two inch straps. I want something I can clip my Tulster Holster that uses a 1.5 inch clip into. Currently Im using the included one that I just cut to 1.5 inches. It works but it will unravel with use. Does anyone know of a good solution to my problem? Thanks for your time. via /r/CCW http://ift.tt/1UpBcNF