Sometimes I can be such a cheapskate! I have no problem spending $30 on a new set of SU! stamps, but $4 for a piece of cardboard? No thanks, I'll make my own.
To make my own bow easy, I used one of the plastic paper dividers that came with my Cropper Hopper 12x12 paper storage units. I printed off a copy of a bow easy, and measured all the little tabs to get a rough idea of how big to make them. You can certainly make them any size you want. Then I just drew the lines in with a pencil and cut them with a pair of generic scissors. The plastic is really easy to cut, so no need to use anything heavy duty. I used my Crop-a Dile to punch a hole at the top of each slit to round it a little. I also rounded the outer corners with the scissors. On mine, the small slits are 1/8", and the larger ones are 3/16" and 5/16".
I will probably only use it when I make double bows, but at least it was free!
Have yourself a great day!