I ordered the blades on line and had them delivered to the store. It took 5 minuets to pick them up. Once I logged onto the store kiosk, the employee brought them right out. The blades were easily replaced in my unit.
There is a standard utility knife with blades made in 3 or 4 quality grades including titanium plated. Not for Craftsman tools, though. Sears designed the blade holder for a narrower blade than standard utility knife blades. If you try to ft a good blade to a 37310 or 37300, it will be slanted in the slot, not straight. Only the narrow blade shown here will work. And as everyone else notes, these are thin and breakable. Good for twigs and branches up to 1/2" but nothing larger.
Works quite good with fresh blades, but blades get old fast.