Just checked the dimensions given by Emgee above against my own Unimat 3 milling table. That table would work on my Unimat 3, even though the mounting holes are a slightly different spacing. It would work because the cross slide of the Unimat 3 has a T slot, so the slightly different hole spacing would not matter. The table mounts either across or along using two of the holes.
There does seem to be a difference in the T slots. Mine are 4mm where the ones given by Emgee are 3mm, eg both the length of the stem of the T and the thickness of the top of the T. So my T nuts would not fit into Emgee's T slots. This would only matter if you already have the same T nuts as me.
John