I've also founds this:
CNT Racing V2 370z Catback Exhaust (Sound clip, Pictures included)
Seems like a knock-off of the HKS and at 800 bucks, seems like a great deal. As far as i know, the HKS and CNT both have 60mm piping and 120mm tips, and the design looks very similar. Might wait before the CNT is in production before ordering.