ArtMetal

I have actually welded cast iron (not brazed ) and you use a cast iron rod to do it.  It takes a flux and is a gas torch system.  Welding rods are available at welding shops and they can give you more details.   It is a bit tricky but much of the key is in using reflective heat shields around the piece and taking the whole of the unit slowly up in temperaure ... doing the weld with the rod and then very slowly letting it go back down in temperature.  For a small piece  I used glass building insulation under it, and old fire bricks to support  the sections together while heating up and letting it go back down again.

 I should think some hands on words from your local welding shop would be very valuable especially if you can take the item in and ask for better detailing about it.  Don't be shy about asking... Good luck  bpfink