Illustrations for a children's book

I have written a children's book which requires approximately 21 pages of illustrations and focuses on my dog and his friends of many shapes, sizes, colors, and ages. I need illustrations which are imaginative and creative and bring my dog and his friend's imaginative adventures to life. I don't have a specific medium in mind and am leaving that to the experts to decide, however as I am targeting younger children for this book, the more fun, vibrant, colorful, and attention grabbing, the better. I'm hoping the illustrator for this project has a passion for animals (specifically dogs) as that is the heart of this book and I know it will shine through in the corresponding illustrations. I have attached photos of the characters and a couple of pages from the book. I am looking to have illustrations completed for the book within 3-4 weeks. There is a potential this will also lead to other corresponding graphics needed for a website in the future.