Repairing a Zinc casting

I hope this is the right subforum for this.  I would like to find a way to repair the tab that turns the ignition switch in a '94 Saturn.  I think it is made of a zinc alloy, and an overzealous helper cranked on it and broke it.

I tried JB Weld which worked for a time, but broke on the coldest January day.

If it's not fixable, I think the only alternative is going to be to find the whole ignition assembly out of a junked '92 - '94 Saturn.  They are long discontinued and I can't find one anywhere.

Edit:  I'm aware of the danger posed by zinc fumes, but was wondering if this might be braze-able?

Zinc melts at too low a temperature for brazing with typical brass filler. It could be welded I suspect, but would take a steady hand and a tig rig that can get down to some low amperage.

An alternative might be to make a replacement in steel. A lathe would get you most of the way there and some careful filing could get you to a finished product. 

A chrome shop can probably fix it. They've done amazing thing for me with broken zinc trim pieces.