a guy i know that owns a gt500 looked into the kr parts and he was told the hood alone would cost 4-5K because of special tooling to design/manufacture the hood.
not sure if i believe their answer, but i believe the guy i know was quoted that.
aside from the mrbodykit one, cervinis has a KR replica hood. and fang performance's mystery 8 hood resembles the kr hood, but also requires their grill fascia.