[Arran]

The leg may have been broken off when it was pitched into the dumpster, or maybe that was the reason it was pitched out. In any event if the leg is not rotten, or insect damaged, then boring a large hole in the leg and the style above it, to accommodate a hardwood dowel, would be the best repair method. In terms of dowel size I would want to use at least a 5/8'' diameter dowel, or up to 3/4'' if it will fit. The trick is drilling the hole straight, for that you would at least want to use a Forstner bit which has a cylindrical shape. Better yet would be if the leg could be mounted in a leg and then riffle bored to fit the dowel. On some cabinets the legs were just held on by a dowel that would fit into holes in the bottom rail, I'm not sure if a model 91 is one of these or not but I think so, in this case it would make it much easier to repair, you would just have to drill out the old dowel and replace it with the new.
Regards
Arran