It doesn't matter where you get the KB, it will be the same price, so just go by there website for pricing.
By the way, I noticed that you have black FR500's. I have thinking about getting the black ones or the chrome ones. Do you have any pics, and what size tires are you running.
I have the pirelli p-zero nero m&s's... 275/35-18 on all four corners... $780 shipped from tirerack.com. and no new pics, my camera has been down and out for a while. I'll be getting a new one in a week or two, and will gladly post some for you.
Its such a bitch to find pics for the black fr500s on a black car, but it look sick.