How much would it cost to replace Leaf springs for a Buick Regal Custom 3800 Series?

For a Buick Regal 3800, how much would it cost to replace the leaf springs?|||no leaf springs are needed should have coil springs and prices vary smarter to call local shops for the lowest quote quick struts come complete with new springs and mounts and just bolt on.|||buy in pairs - www.jcw.com