The only real difference between HICAS and Super HICAS was that Super had an electric actuator motor instead of a hydraulic pump. I can't see why they couldn't be swapped out, but you'll need to make sure you get the computer system that controls the rear actuator pump.
Wikipedia: wrote:Earlier HICAS versions used hydraulics to steer the rear wheels. The hydraulic system was powered by the power steering pump and used speed sensors to determine how much and in which direction to steer the rear wheels. Later versions, called Super HICAS, moved to an electric actuator for the rear steering rack, making the system much lighter. The Super HICAS system also used its own computer to control the system instead of speed sensors.