Not to resurrect a necro thread, but I get a lot of people that contact me directly for parts information on this so I thought I would add the part numbers to try and keep the personal inquiries down.
These are available at McMaster-Carr
The parts numbers are:
#92395A111 Screw-to-Expand Inserts, for Plastics, Brass, 2-56 1 Thread Size.
#90272A081 Zinc-Plated Steel Pan Head Phillips Machine Screw, 1 2-56 Thread, 1/2" Length