there's a lot of factors at play here. how do you want the car to sit? how much height do need to clear whatever wheel & tire combo you have? how do you want the car to perform, what are your expectations for ride quality, and how do you plan to drive it?
i can't just say: oh, install [blank company's] OE XHD +1" 4 leaf and you'll be great because i don't know what all you got cooking.
i will say that an OE style formula S/HD or XHD is probably at or near the spring rate that you'd want to run for a street and sometimes autox car. arch height will be dictated by the look you want and whatever limitations your wheel/tire combo is.
but, you can address height with adjustable spring hangers-- to a certain degree-- without jacking up handling. i would strongly recommend against running anything more than 1" block to get where you need, and even then, i am loathe to suggest blocks.
all of this is to say, the SS springs are not the answer unless the expectation is mainly straight line performance.