I had some black vinyl coated wire coat hangers that I used. I think I purchased at a Dollar store, and have seen them at Walmart.
For me (I am not very strong), I needed some pliers with a long handle to cut it. An alternative is to use a cut-off wheel on a Dremel type rotary tool.
However, I would prefer something hollow so that I can run the wires through the center. But, hollow and bendable is a bit difficult to find. There is brass hollow tubing that used to be available in hobby stores, but is now hard to find. The benefit of brass would be that you can solder pieces together with ordinary solder. You can purchase all sorts of brass at;
http://www3.towerhobbies.com/cgi-bin/wti0097p?CATEGORY=RD&FVSEARCH=BRASS+++
Joe Dunfee