Bought these for my supercharger but wound up using the metal elbows instead. They're not good for the supercharger because the elbow collapses under idle, but maybe they'd be good for something else. I don't remember where I bought them from. $30 shipped.
2x90 deg 3"x3" elbows
90 deg 3"x3.5" elbow
3"x3.5" adapter
2x90 deg 3"x3" elbows
90 deg 3"x3.5" elbow
3"x3.5" adapter