Never mind, I look at the keyword "Copystand" and found a bunch of options
On the section where Bill explains his cross-polarization set-up, he does a wonderful job describing everything except there is no mention on the apparatus (table base system) holding his medium format camera.
I did not think it would be hard to find a similar piece of equipment, but so far no luck. Perhaps not using the right keyword on google.
Any feedback is appreciated!