Mustang 960 Tandem pump

I have a mustang 960 skid steer. My right side drive pump is weak. I called a mustang dealer and they told me the pump was no longer available through mustang. I haven't had any luck finding anything online either. Loaderpartssource.com has 1 but it says it for serial numbers prior to 4625613. My serial number is after that. Does anyone happen to know of any place that I might be able to get 1 from. I would even be willing to buy a used 1 as long as it was guaranteed to work. Any help is...

Mustang 960 Tandem pump

Mustang 960 Tandem pump