Which leaf spring?

A new set of factory replacement springs will automatically give you at least a +1" in height over your old sagging springs,if not more.

My vote...The cheapest (money wise) set of stock replacement springs you can find.

Seen it all the time, where guys get a +1" spring or heavy duty spring, and then complain that it sits to high. Then they ask how to lower it.

JC Whitney use to sell stock replacement springs for cheap.
My favorite springs of all time.