I'm not sure there are many artists we can clearly define as "surrealist fine art illustrators" as much as we can more easily point directly to authors and define their work as surrealistic. A quick google search renders these pages among others:
https://www.hbook.com/?detailStory=picture-book-surrealism
https://www.pinterest.com.au/starryeyedtl/surrealism-in-picture-books/
Interestingly, this page breaks down artistic styles for children's books and offers some example definitions and works: http://www2.nkfust.edu.tw/~emchen/CLit/picturebook_styles.htm
I, personally, have a LOT of trouble differentiating Fine Art from Illustration, and I think in some ways it was a lot easier to do so prior to WWI. After that, things get convoluted. So much of it has to do with the artist's/illustrator's intent. And today, I think so many artists straddle both worlds that differentiating the two is even harder.
But there are artists out there that lean into styles that are inspired by Fine Art methods. Marco Bucci, for example, is a straight-up Impressionist with a capital "I" if I've ever seen one.