I have an illustrated podcast novel at www.cowrycatchers.com. It's available in text or fullcast audio. I pay for illustrations in the $60-120 range, sometimes more, depending. Examples are here: [link]
I do like artists to engage with the story and chose the scene they want to illustrate. I pay you promptly, and I'm usually a repeat customer.
If this looks like a story you'd enjoy illustrating, please note/message me or contact me on my website.