The Ecotec Motor that is in the reg SS is a 2.4L and the Ecotec in the Supercharged SS is a 2.0L.
You could buy the 2.4L because there are a lot of superchargers out there for that motor but its not going to have the beefed up features as the Supercharged SS.
Not to mention, you will void your brand new 5yr-100,000 mile powertrain warranty.