I am trying to do this on a budget ..my bobcat 641 stopped moving my mechanic friend said it was the drive pump went bad so he pulled it off I drove 75 miles to a hydraulic pump rebuilder the called and said the pump was missing a piece called a dog bone my mechanic said he didn't see it and bobcat don't make or sell them so they said I have to buy a hold new one that cost about 1500 I have seen a couple of used one on eBay but was not sure of the fitment so I called the rebuilder to get a part number of pump and he just won't send ...need some help so if anybody can tell me what to do let me know or a part number