I know I've seen them... where?
"Kindness is free" ~ Eurofoal
The CoTH CYA - please consult w/your veterinarian under any and all circumstances.
They used to sell them for Easyboots. Pretty sure they have been discontinued. I have a pair to fit a 00, you could have them if you want. Couldn't you use a regular wedge pad and cut it to fit?
Use the same wedge pads made for shoes - you'll have far more options that way.
Balanced Hoof Care for Performance & Rehabilitation
This is all I've seen Easy Boot
These don't look very wedgey to me.
These are very interesting. I think they would work wonderfully in a boot.