Not trying to upset the cart here.......although I think those look really great......I purchased one from Bob Ida Automotive many years ago, and had him install it.........I dont remember that the installation cost as much as $500......but people here know more than I,.........The last I checked with Ida Automotive he did have about 5 or 6 left..........I dont know how much he wants for them...but if it helps I paid $750.00, and had to give him the cap off the car. The caps that were ingraved were purchased from Ford....so they are NOS.
His shop is in Morganville New Jersey.........I dont have his number, but I guess a little googoling will find it.
Gino
P.S. At the time he did tell me that whom ever made them spent a lot of time on these to get them perfect.