I ordered some and they are good. They are back to $1.99/2 pack [~ $1.00 per blade). I ordered 8 packs at the sale price of $1.79 (there was a $3 difference between ordering 8 packs or the next higher quantity), but even with shipping, they are cheaper than the others, which seem to average about $3/blade before taxes or shipping. They only fit the 45mm rotary cutter.
Also, as someone else already mentioned, they are listed as carpet cutter blades and are in the flooring or speciality sections of the Harbor Freight catalog or store.