What is a good replacement for the rear springs?
You have two choices. The best, and more expensive choice is to buy Ground Control coil overs which come with a variety of Eibach springs. Or, you can buy a set of Integra or Civic Wagon springs from the junkyard. On my car, I have the stock torsion bars and a set of Integra springs with one coil cut off. This combination works well.