Open Education Resources or Open Textbooks have an open license that permits free distribution of and access to course materials for the public. These books are available in multiple formats, including print, audio, and eBook. Ask your professor if they are willing to adopt this option for the course. It will make obtaining materials easier for everyone.
Here is an example of how the open textbook will look:
Credit: https://openstax.org/books/principles-macroeconomics-3e/pages/1-introduction