you might have to make your own, are you going to convert to EFI or stay carbed? if carbed, you will need a custom blow thru carb for your application depending on engine size and final boost psi.
what is your budget? and what is your final goal for the car? (mainly street, street/strip, drag only, weekend cruiser, show car, etc?)
this is why I like nitrous instead... simple, cheap, fast.