Where Can I get A Differential
 

I tried searching google, for sever hours, but came up with nothing.

It would be great if it had an input hole or shaft that fits the 8mm keystock on the chippawua.

thanks in advance
Matt

Finding a supplier for a differential as custom as that is may not be feasable. Your best option to get what you want is to design it and fabricate it yourself. We don't have the tools to do that on our team, but many teams do.

Your other option would be to design it and contract the construction to a local metal shop.