SawStop cartridges are ~$70 USD. Not very expensive -- your hands are worth far more!
http://www.amazon.com/SawStop-TSBC-10R2-Cartridge-10-Inch-Bl...
http://www.amazon.com/SawStop-TSBC-10R2-Cartridge-10-Inch-Bl...
http://www.fairwarning.org/2013/05/after-more-than-a-decade-...