Hello
Sorry to hear it got broken, bummer!
I personally would search for a replacement arm! This would be your best SAFEST bet, as it would be 100% again, I've seen several of those parts around, pretty common repair! And fairly cheap as well!
( this will also insure all your plains ( horizontal, verticle ) will be level and true.( this in my recommendation to you! ) but also my opinion, please do what you want, only advice to you!
If you are set on mending part
( I don't recommend ) as stated before, if it glues out of level or slightly off center, your camera may not level out correctly? ( you might get lucky! )
Plus if joint fails you stand a chance of loosing a $300 camera, so that $20 part ain't a bad buy!
If I were to try a repair,
I would use 2 part epoxy, as the parts are aluminum ( I call it pot metal ) as it is a low grade cast aluminum ( cannot weld or braze it ) epoxy is strong stuff! Most likely does not matter what epoxy you use, as long as it bonds to metal!
Good luck, and keep us informed!
Hope this helps!
J Dot
