There really are no dedicated leads in BW. Disregarding that, the goal of that Tyranitar is to set up Stealth Rock, hit hard, and lure Steels. It's hard to fit that same niche so instead I'll give you other options. Here are Stealth Rock users with various benefits:
High attacking power - Gigalith, Bisharp, Mamoswine, Aggron
High defensive bulk - Steelix, Skarmory, Bastiodon, Deoxys-D
High Speed - Aerodactyl, Dugtrio
Steel killing ability - Azelf, Infernape, Heatran
Or the traditional Metagross, Bronzong, Celebi, Jirachi