source for KNO3 and K2SO4

Three weeks ago I placed an order with PCI Scientific supply for KNO3 and 
K2SO4.  This was one of the  sources listed in a posting Jan. 6. Three weeks 
passed without receiving my shipment, so I called to follow up.  After a few 
calls I was finally told that they would no longer be shipping chemicals to 
individuals because of the explosive nature of the chemicals.  Seems PMDD 
ingredients are getting tougher to find.  Maybe I'll see what I can find at the 
local garden centers.