Hey man,
I'm in the same boat as you, I LOVE those wheels
They were Manufactured by Alcoa (I believe Alcoa only made these wheels with Shelby...correct me if I'm wrong)...So they are in limited supply at the moment, which could be why they are going for around $500 a wheel (yea, makes me mad too)...I love them soo much, but Shelby patented them I believe, so I do not know of any replicas at this time. IMO, I would this it would be easy to replicate these wheels, of course not forging them or having the durabright on them would help bring down the price a bit
Anyways, try contacting Mike over at
Mustang GT500 Carroll Shelby Wheels - CS40, CS66, Alcoa GT500 Super Snake Wheels
Or you could go straight to the source:
Wheel & Alcoa Wheel - Shelby Performance Parts LLC.
I hope I helped, and great luck

...great looking 09' btw