Darn bionic mice!

You will find the connectors available at most auto parts stores but they might have to order them. They have huge catalogs full of them.

I would trot down to my favorite pick-your-own-parts salvage yard and snip off the connectors you need with plenty of wire. The proper repair involves cutting back all wires until you find the copper is shiny. Dull copper means the solder won't stick. Slide on a piece of heat-shrink tubing onto one of the wires, cut 1/4" of insulation from each wire. Push the strands together so they slide between each other. Do not twist them like we do with house electrical splices. Be sure there's no sharp points sticking up because those will pierce the heat-shrink tubing. Heat the connection on one side with the soldering iron, then apply the solder to the other side. When it melts it will flow through the joint toward the heat source. Once it cools, slide the heat-shrink tubing over the joint and warm it with a match of hot air gun.