Hi there,
you seem to be looking for rather simple line art, so I would be happy to offer handcrafted pen and ink original drawings for your colouring book. My bid would cover pack of 5 designs of similar complexity as the samples provided. I can also offer more detailed illustrations that would cost around 35 USD per piece (for examples, please check https://www.freelancer.com/u/ddimitrovska.html where three of my line art designs are available).
If you are interested, please write back to discuss details.
All the best,
Dusica