It wouldn't be practical to cut a horse's foot off for a good luck charm, nor do I belive that it even is a good luck charm. But, let's say this design is a good luck charm to save a horse. 
Color ideally, open to black and grey. 
Ideal location: arms/legs 
 
IF YOU ARE UNABLE TO PAY IN FULL, $100 DEPOSIT IS REQUIRED TO CLAIM THIS BEAST. EMAIL ASAP. FIRST COME FIRST SERVE. Dicussin of payment will be dicussed via email. Once the deposit is made and the appointment is set- this will be removed from the website. And then it's yours. And you'll be the coolest kid on the block.