The thing to search for in terms of the period between the hand-illuminated manuscript and the illustrated printed book is
inncanabula
And printed illustrated books weren't rare; they were fairly common.
People who read books expected them to be both decorated and illustrated as so very many mss. were.
Keep in mind that by the 1400s in Europe workshops were mass producing, assembly line style, manuscripts, particularly those of really popular texts.
By the time of the Really Famous and Popular printed books printed in England and in English by Caxton, the two "best sellers" Caxton's Malory and Chaucer were illustrated with block prints.
That is, an image was carved into a specially prepared and surfaced block of wood (today they're blocks of chip board covered with linoleoum like stuff).
The block was inked thoroughly, then a sheet of paper was placed over it, fixed in place, and a roller was used to carefully disperse the ink onto the paper.
In some cases, this was used exactly like stamps are used today, where a series of wood cuts was carefully placed to create a "scene" or image.
In many cases these illustrations were hand colored before being bound into a book for a wealthy patron.
Then in the mid 1500s, especially in Holland and Belgium, and a bit later, Italy, intaglio printing, a sort of cross between engraving and printing, that used a dedicated press just for illustrations.
(Today, a lot of the really best examples of intaglio illustrations in books are not on public display because they're pornographic/erotic).
The next step was engraving and etching (with acid) on plates;this started to quickly replace intaglio in the late 1500s because it produced better quality results, faster and cheaper. The most famous instances of these are those of William Blake. These were easier to mass produce, but they too were frequently hand colored.
Asia, especially Japan, was way way ahead of Europe in terms of printing illustrations.
You can make paper of spinach and lettuce with just a little linen or cotton or papyrus added for fiber.
In Russia in the middle ages, birch bark was used for paper, particularly for things like letters or journals.
And rice makes all kinds of amazing paper.