Not sure about your diag on the trans, as I'm having trouble visualizing what you've done. In any case, when I get a new machine unfamiliar to me the order of business is to check all fluids, check all safety related items (brakes, steering components), then run test and drive test). I didn't read the whole thread so I'm not familiar with what's all missing from your machine, I'm just recommending you don't dump too much cash into it without knowing what's actually wrong with the machine.
Regarding parts, if the part was also used in a civilian model I would have told you. All the part numbers I've provided are exclusive to the MRZR diesel platform and are not shared with any commerical counterparts, nor are there aftermarket options available.
edit: I realize you may be attempting to jimmy rig it with commercially available pulleys - if so, I wish you luck and do hope you succeed. Have you gotten the unit running yet?