These can be bought as a set for $129.90 at dover saddlery. I used them around 3 times and they were cleaned directly after each time I used them. They are in excellent shape-- practically new. These are white and horse sized however, i have found they fit a wide variety of horses.
If you wish to purchase just one of the set (just the ankle boots or just the front boots) then the open fronts are $70 and the ankle boots are $40.