Found this while searching today:

http://www.versatool.com/shopmight.htm
http://www.versatool.com/shopmight-accessories.htm
They want $500 plus shipping for it, no saw. Im betting I could buy the extruded aluminum and build it myself for half that. I would have to drive up to my old work to do some machining, but still is cheaper than what they are asking.
I could just buy the two rails and make my own carriage and mount it on a wood base also...
Just thought I would post up this option for anyone else who may be interested. If I build one may as well make enough parts for 2 while Im set up.