I've got a granite block and am set to try the "Scary Sharp" sharpening
technique on my planes and chisels.

I'll evidently require most of the standard grits of Wet or Dry (silicon
carbide) Sandpaper between 100 and 1200 (or so).

I obviously don't need box of 50 sheets of 100 grit, and 50 sheets of
150 grit, etc. (at $17.95 a box...).

Can anyone refer me to a site (or store) where I will be able to buy
several grits in a package (like 100, 150, 220), or (320, 500, 800), or
by the sheet, or any other way that makes more sense for my present needs.

Thank you,
Bill