Circling back on this . . .
I had a length of 1/2" copper pipe on hand, so I cut it to size, hammered the ends and ground out the screw slot. I used an insulated clamp from HD's electrical dept. to attach the rod to the leg. I'll have to do a little fine tuning, but 10 minutes of work and $1.68 in parts got it functional.
The overall length of the support rod is 18". The original is made of 1/2" round stock aluminum. Both ends (1") are crimped flat with U cut outs to fit over the screws of the leg clamps and shelf bracket. The crimped ends are positioned 90 degrees opposite each other.