Hi,
  I assume by grousers, you mean the pads. If want whole new pads, I would try Zimmerman Oliver/ Cletrac in Pensylvania for starters, if he does not have what you need, I would suspect he can point you in the right direction. Phone # is 717-738-2573
    If you just want to build up the Grousers, there is steel bar made for grouser material.  You cut it to length and weld it on to the worn grouser...I can promise you, it is expensive material. It saves a lot of time tho', as it can be done right on the dozer. Pads do not have to come off <!-- s:) --><img src="{SMILIES_PATH}/icon_smile.gif" alt=":)" title="Smile" /><!-- s:) --> 
              Cal