Try www.servis-rhino.com. What are you looking for? How much area are you shredding? What size tractor are you using?
I owned the equivalent of the Rhino SE-7 and traded up for a TW-120. Both are excellent shredders. I prefer a 3-point hitch style but you need enough tractor to handle it. Rhino has what they call a semi-mount that uses the lower pull arms at the front and a hydraulic cylinder suporting the rear. Works okay but there are disadvantages. They also have a standard 3-point hitch and a tow type.
I also looked at Bush Hog. They are comparable machines.