What, do you think I bought these at Home Depot or something?
Just look at the weird fasteners they supplied in the kit. Flat-head screws with highly unusual square socket heads. The 5 screws and nuts to fasten the 5 brackets to the plastics and 5 wood screws to attach them to whatever you want.
I don't even know where you would buy them. I doubt you'll find them at Home Depot or Lowes. I don't have any square Allen wrenches to tighten them either.
Now look at these pictures taken from the CPR website. Notice the screw heads.
It looks like maybe CPR provided them with the first batch of plastics but maybe ran out of them or something. I purchased three sets along with a playfield and a backglass and they all had the hardware. I still have all three toppers.