[ABM2SS]

Been searching old threads but fell I'm wasting time.
My 2010 SS still has original Suspension and Struts, but at 278,000 miles she's feeling pretty worn-out. I don't want to lower the car, but I want to upgrade rather than replace with original parts. Can someone either give a recommendation for an aftermarket company that will help me select the best parts for my application or point me to an old thread with that information?

Also I plan on buying aftermarket rims and going to a square set-up --> 20x10 + 35 offset wheels with P275/40 20 tires