A simpler method, and probably less cost-consuming would be to save up old-fashioned wire coat hangers; they can be cut to the length you want, and can be painted black (or other colors for chromakey/bluescreen-greenscreen work), while similar colored duct or masking tape can be wrapped around the ends for makeshift handles.
I am aware that it's a painfully primitive, and quite amateur way of obtaining armrods, but it is quite effective irregardless; remember even Cheryl Henson reminded us that even if a puppet is made of simple materials, the important thing is the character and personality.