We recently bought these components from the estate of a New York jewelry designer. They are all heavy-gauge Sterling Silver. See the third photo for the full collection.
The triple-strand clasp measures 1" wide and 1-1/2" long. In today's market, it would be $24. It has a graceful fleur-de-leis motif and a substantial hook and eye. It is for a triple-strand necklace, but it will accommodate a single strand and stay balanced on the middle loop.
Price is for one clasp. Will go to the site for $18 on June 1.