Yeah, that $550 includes all the piping for a near bolt-in.
However, there's nothing wrong with saving some coin and doing it yourself. EBay has some nice Bar and Plate I/C's for the $130 range (+/- depending on size), these are just as good as any of the other's I've seen. The Volvo I/C is a very popular item, but that's about all I can think of from a junk yard. Some Audi's might have come with I/C's but I don't know for sure. Hit up the import section, that's your best bet, you might even find a nice blow off valve from a DSM or an external waste gate from an Audi.