Springs out of hose clamps? I've tried it but couldn't get it to work very well. When you don't know the material that you're using oh, it becomes very difficult to find the right heat treat / temper. At best we can hope for a backup piece.
Making Springs is really an art form. Out of the dozens of times I've tried it, I think I had two that actually functioned acceptable... Not good, but acceptable. Maybe find an old gunsmith that knows how to make them, maybe a knife maker? I tried looking for decent instructions / video... Haven't found anything decent yet.