Not that I've ever seen. Another option would be to reuse the oem mounts or try to find some new/low mileage 11-14 take-off mounts but that won't be as strong as gt500 mounts! Best bet would be to get the 05-10 Koni's.
-2012 Mustang 5.0- Stock (for now)
-2013 Mustang 3.7 (SOLD)- Best 1/8: 9.057 @ 80.67mph