If it looks like this picture, you'd be better off taking that piece of garbage to the recycling center and running away with any money they might give you for it. If it's HKS's new bellmouth design, that's a different story, but it doesn't sound like it is. If you're looking for a relatively inexpensive downpipe, check out Invidia's bellmouth pipe. They make a decent product at a reasonable price.
07 WRX (Albins 5MT + Blouch 20G)
Jorge Carrillo Tuned (365 whp/340 wtq)