I used a cast iron engineering angle plate for mine. Yes it is heavy, but on the DF700, it counterbalances the weight of the machine nicely that it won't fall off the edge. I have a M8 T handle coming for it, and will put a slot into it for looking at the alignment mark on the machine base.
The longer side is parallel to the cutter face, and the shorter side connects to the machine base. In the Picture, I have a 9.3mm thick acrylic sheet as my spacer to get the 9mm centreline for the 18mm stock I was using at the time.
It is about the same price as a Bigfoot and weighs about 4.5 kg. it is 145mm wide, 110 high, 122mm long. The 122 long is on the work face, which will get the T handle at the front of it. It is Vertex brand from Taiwan.
I am also going to make some eraser rubber inserts in the plate to act a grippers, like what is on the front face of the Domino machine.
It does not easily fit into the Systainer box safely. At the moment been keeping it with the clamps and the Extension arm set for the Domino system.
Edit dimensions for angle plate. 145mm wide, 110 high , 122 long, Vertex brand, from Taiwan.