[_tom_]

Open source textbooks are available and usable online for free. Why do you need printed copies?

Frequently, open source textbooks can also be printed on demand for much less than the cost of a new textbook, in any quantity. If you can afford new books, you can certainly afford printed old books.

“Out of print” is largely an outdated term, except for small print run books. If they sold well new, they should be available used, in quantity. Especially if you are only replacing lost or damaged books.

Project Gutenberg has many old books online and you can get them printed.