I have a sweet grass Turkey who lost her foot early on in her life, and just has a stump now, her name is Peggy. We created a series of prosthetics with clear aquarium tubing. Just slide the snug fitting tube up the stump to the joint, and cut it off at about the length where the foot would be, and both legs are now the same length! We have had to increase the size of the tubing as she grew, and you cant leave it on indefinitly, but she tends to loose it every week or so. I usually get it one size too big, cause I dont want it constricting her leg.
She gets around well, both with and without it, but she is definitly a bit of an outcast. The other turkeys dont acknowledge her existence, and the hens dont like her, so she is living with a group of Juvinile Cochins, who of course love and welcome everyone, so she is happy. But I do have to keep an eye on her, and make sure she hasnt been driven into the bushes or under something by an overly protective mommy hen. But she is worth it.
I fear tho, that as she gets bigger, she may not do so well, fortunately she is a heritage breed, and will not get 40 lbs! We shall have to wait and see.
Good luck with your little one, and try the tubing, it works well.