About to do a waterseal-rebuild and allready in trouble!

I just can't remove the pulley on the servo pump! I spent good money and time on ordering the SST for holding the pulley while removing the center-locknut.. Well, the SST-holes on the pulley cracked as soon as I applied a little force to it! I've been able to jam the pulley, but as soon as I try to loosen the nut that plastic pulley-**** just cracks more..

Any ideas? Anyone know if there are any atermarket non-plastic pulleys I can replace it with? (if I ever get it of)