A nice source of Spring Steel is old, leg-hold Traps. I bought a large box of them at auction several years ago. Literally years worth of spring material. Due to the variety of the sizes of their component parts, it's easy to select a piece close to the size you need. After cutting off the sized piece you need, annealing, and "having at it" with a large Bastard File makes initial shaping go fairly guickly. You can shift a lot of metal with one in a very short time.

Regards
Ken

I prefer wood to plastic, leather to nylon, waxed cotton to Gore-Tex, and split bamboo to graphite.