Not sure where you're looking to get them, but you can pick up the 1"x8" 100 grit or 150 grit wheels on Amazon for $30 with Prime.

I have at least two pairs of the stock 1x8 wheels that come on the Rikon 80-805 grinders (60 & 120 grits). They're not Norton wheels, but if you want a set, DM me and help me get rid of items I'll never use :)