You could make a jig but that would require welding or a jig table or some real creative thinking with wood. Jig + Heat would look the best.

Or you could use an oxy/acet torch and heat it then bend... since it's 1/2" you could probably get by with MAP Gas torch from home depot... or maybe even propane since it's not much cooler and 1/2" round rebar is not the strongest