I'd try to make something like this with wire coat hangers. Calligraphy initial necklace - A single piece of sterling silver wire is looped, shaped & hammered to create each of these beautiful initials. Each letter measures 1 inches. By Laladesignstudio
How To Make A Bead and Wire Toggle and Bar Clasp - The Beading Gem's Journal.The relative sizes of the bar and toggle will depend on personal preference and the actual jewelry design. So try it out with some copper wire first.