I was reading up on BeanAnimals just two days ago and noticed the same thing in pictures that the folks were using sanitary T's in PVC.
Around here, easy to find in ABS, and probably completely impossible to find in PVC. Give the folks at Western Pump a call, maybe they have something but to be honest I doubt it. Beyond that maybe some kind of irrigation supply place. Speciality PVC bits around here are hard to come by.
I did find a mail order place just now but no idea if you have to do a minimum order.
http://www.pexsupply.com/PVC-Sanitar...All-Hub-475000
Good luck.
PS. In my own FOWLR that I was about to do the BeanAnimal on, I ended up saying "screw that" and just went with a modified Herbie (two emergency overflows but otherwise is a standard Herbie). Herbie's are silent and bubble-less anyhow and I have no cause to complain about the one in use on my reef so some food for thought for you on that one.