I am preparing to install a Clearvue 1800 Cyclone, so I started the odyssey of searching for the hard to get 6" PVC S&D piping (ASTM 2729). I am in Southern Connecticut and I found Ferguson Waterworks @ 203-384-9402. They have the pipe, 45 degree elbows, couplers, and 6X6X4 wyes. The prices are very attractive (less than McMasters) and they they will sell to non business people. More importantly, they are nationwide and the following link will get you to a local office. I dealt with Ryan Radiochi and he was very helpful especially since my order will not be that large.

http://www.ferguson.com/

I hope this is of some value.