If the contact area is small, then I'd be inclined to drill holes into the opposing surfaces and glue in a steel pin.
ETA - Accuracy in getting the holes exactly opposite each other isn't as important as you might think. If you give it your best shot, use a pin that's narrower than the holes you've drilled, and the adhesive will fill in the gaps.
If the contact area is small, then I'd be inclined to drill holes into the opposing surfaces and glue in a steel pin.
ETA - Accuracy in getting the holes exactly opposite each other isn't as important as you might think. If you give it your best shot, use a pin that's narrower than the holes you've drilled, and the adhesive will fill in the gaps.