I would try either the JB weld or some 5 minute epoxy, also fill the tube with a solid material with a press fit, something for the pin to hold onto. More extensively, there are materials available to solder aluminum
I remember a resin caster that made all kinds of truck replacement parts and 4x4 conversions. I'm not sure if it is fron the aftermarket directory or not, but I'd bet they have what you're after.