I'm not trying to be a thread necromancer, but I just came across this thread today. I used to work for the company that produces the tracks and undercarriage for those tractors. More specifically the plant I worked in produced the tracks, idler wheel(front), midrollers(middle) and large drivers(rear) that are on it.
Those tracks are built on a giant collaspeable mandrel, assembled much like a rubber tire with layers of rubber and cable built into them and then cured in a Hydroclave that is just a giant pressure cooker. One of my jobs at Camoplast was to run the hydroclave and then disassemble the mandrel to pull the belts off of them with what looked like a giant claw, from one of those claw games. Then I had to inspect them, make corrections, and then suitcase them so that they could be shipped. The belts that are made for those tractors are a pain in the butt to suitcase because of their narrow guideblocks. When the suitcase arms come into to fold the belt together you have to match up the guideblocks so they rest against each other. The problem is that they have about a 2 inch surface area to go against each other and if they are a narrow belt...they can get a little squirrelly.
It looks like those are either 28" or 30" wide tracks, which were relatively easy to suitcase. Camoplast makes up to a 36" wide track, but most of those go to different manufacturers. They produce belts for Cat, John Deere, Agco, Case IH, CNH, ATI, and a variety of others including those for construction and military.