Ford Dealership. That one looks exactly like the one I have on my Mustang except minus the GT. But the Mustang signature in red is there. That is also one part of the two part bra with the other part covering the front bumper cover. The cost was a little over $100 bones. But I have always found the Dealership bras hold up a lot better than the third party crap.
The dealership will more than likely have to order it for old model vehicles. You can see the bra in my signature picture. The Mustang signature is in the same place, but you can't see it in the picture.