Jerry,
The original bushings were rubber, with some "give" to them to soak up some road vibration and allow a bit of movement as the springs flex. I doubt that Teflon would be resilient enough to allow those functions. That and I don't have a lathe available (yet). I tried to find some bushings with integral washers at Energy Suspension, but they didn't have the correct size.
Once I got the material selection right, casting the bushings with integral washers wasn't that hard. I believe this time, they'll work just fine. If not, I can go for the revulcanization from Steele and the $50 rubber washers. But being a cheapskate, I had to try this approach.