I think that the price is dictated by availability more so than origionality. My guess is that the availibility is quite limited; otherwise, eveyone would be coming out of the woodwork to collect their 600 bucks.
This is purely a case of supply and demand, and they look nice in the pictures. If I were putting togehter a ram air car and money wasn't an obstical, I'd have a set to complete the car, and I wouldn't car whether or not they are correct.