Looking at the book it does seem relatively simple and I believe you'd easily be able to convert it to a textual Epub as opposed to one containing images.
There are some basic tutorials on creating epubs; for instance see
https://wiki.mobileread.com/wiki/EPub_Tutorial
Another item to check (I'm on a phone right now so can't check); how are those images saved (not really sure of the technical term to use). RGB or CMYK?