Yep, I actually missed it the first time I looked. This one specifically is the one I have.
https://www.svst.com/Boots/Foam-Boot-Fitting-Aids/Tapered-Shin-Pads-5-5Pr.html
Unless that one is soft foam. The picture shows it on the inside of the boot. Mine is definitely hard foam and goes on the outside. 1/2” is the correct thickness though.