In my experience with main springs for antique firearms, if you bend without heating to the point that it retains a new form, there will be cracks in the spring that will almost immediately fail in use...in other words anneal then bend, then re-heat treat, then re-temper.
ohh ya...drill your hole in the annealed state.
Brownells sells flat spring stock (a local gunsmith may have a selection close by...Stel...) in its annealed state that you can make your own new spring from , comes with "how to torch heat treat" directions that most home shop gunsmiths will use because of equipment limitations.