I took the OEM rubber dive strap off my GSAR as soon as I got it. It was never worn. The strap is 20mm 3/4" in width. This retails for fifty bucks plus shipping. http://www.countycomm.com/sarstraprubber.html
This is yours for forty bucks shipped CONUS.
Pay Pal works best, a postal money order, personal check or cash works too.