From what you say a new sub would be in order, one with more power and larger woofer so it can take more abuse or fulfill your user demand. It sounds like that system may have been a matched set where they usually run the crossover a bit higher than a typical sub but most new subs will have a variable crossover for a fairly smooth integration with your satelite speakers. If you watch movies through this system a sub is in order but you might want to also think of getting some larger tower speakers for the front as well. With both larger mains and a larger sub you should be able to rock with Rush without incident. Well, as long as you don't run your receiver beyond what it's capable of doing.

What size is the room and what budget would you be in? Check out the SVS website.