A buddy of mine has a 2012 SS and he just got a quote of 1300$ EA from Shelby And that is for a 20x11. I assume the fronts being smaller may be a little cheaper. But if not that’s 5200$ for four new with the Shelby SS engravings.
I have a brand new in the box from Shelby original KR carbon fiber front splitter if your interested. I bought it but changed my mind going different route.