Is the other wire broken off up inside? , I was wondering if you could see any wire or contacts up in there? Since it is broken anyways, I would take a chance and see if I could get a piece of a conductive material (solid copper wire or such) to snugly fit in there and make contact. then would solder and /or tape the other wires back..
I think that bulb's socket case twists into the dash's hole to hold it in place.. because of that is probably is a kubota only item. I have though, bought new bulbs like that at the auto parts store. collie