Realistic Farm Animal Illustrations for Sweatshirts

I'm looking for an illustrator to create realistic vintage graphics of farm animals - specifically cows, pigs, and chickens - for sweatshirts. The animals should be depicted without a background, as isolated figures. The illustrations need to be in pencil line style. This project requires an understanding of realistic animal depictions and the ability to create designs suitable for clothing. A portfolio demonstrating prior work with both realistic illustrations and apparel graphics will be highly regarded.