New Springs

Not sure why you wouldn't want steel from some of the newest, most technologically sophisticated steel mills in the world, but to each his own.

No matter which springs you decide on, do yourself a favor and use fresh bushing and lube them and your new rear shock's bushings with some synthetic disc brake grease. The rear suspension will work with much less stiction. Be sure to use fresh u-bolts and nuts too, and re-torque them a few times too.