Plumber's strap or look in the metals section at your hardware store. You can find flat bar with holes in it. Cut it to length, bend as required. Sounds like you are working for the hose clamp, rather than it working for you. I believe it is made out of spring steel. Get something made out of mild steel so that you can work it. That spring steel has already been worked so it is REALLY hard to work it more, as you've found out.
Bill
