I'm thinking $500 or so... the only thing I don't have is the bolts that hold the shroud in place, because I never used the shroud... in fact, I'll have to see if I can find that. I'm sure it's somewhere in my apartment. it's the 3.5" by the way.
Without the shroud you weren't drawing properly. There is more air drawn over the TMIC than pushed. Without the gasketing you're getting half what you should.