Uh, thats quite the hefty pricetag for a simple fertilizer found most everywhere..
I just buy nitrate of soda,by hi-yield (they also sell copperas, and potassium nitrate [-stump killer]), recrystalize it, and Im good to go.
KNO3 works fine too. It is sold as spectracide stump remover.
SMB can also be sold as stump remover, except under the brand name bonide. MSDS are your best friend, er, SDS now (I guess)
Also, these names are only good for people in the US and Canadia. Across the pond, no idear.