Dimension SST Printer Broken parts
Seeing as how no one has been able to find a solution yet and I'm not familiar with your machine, I would recommend reverse engineering the part to the best of your abilities. If you don't have the right tools, try finding a local machine shop and ask if you can use their measuring equipment. Sometimes you might get lucky and they will have something more intuitive than callipers, such as a CNC CMM or CMM Arm. As far as acquiring the part, try asking the machine shop if they can produce it, or get it 3D printed via 3D Hubs, MakeXYZ, or some other peer printing service.

I'm sorry I don't have a more direct solution, but hopefully it at least a general sense of what options you may have.