for lifting the rear by replacing the rear coils, while still using the stock shocks.....i think the only thing out there are the pp springs. they are $199 for the set for the rear.
if you do that, you will gain about 1.25" of lift, and to take care of the raked look, you can get a 1" spacer for the front. that would be easy, and give you 1" up front, and 1.25" in the rear.
or...you can just get used or new oem coils, put them in, and see if they sag again, or if it is just a bad set you have. if they do, then just get the spacer from jason. that would be the cheapest way to go.