The picture shows that it's the 3-phase version, just FYI. These are nice machines to put a VFD on (but you DO need a nema 4x one around grinding dust, so figure on $300-400 all in), or you could always switch out the motor for much less...I think they're a common 56c frame, but don't quote me.
I would be very surprised if the guards were not still available for purchase. I have a pair of Burr King 760's... I'm very, very concerned about shop safety, but I sometimes prefer using my 760 with the old style (read: very minimal) guarding since there's not much to get in the way, vibrate and make noise, etc.