The Ignatius Press Vision series on the saints is one possibility. But if you are open to allowing your son to read fiction in general, and not just by Catholics, see the book below for reading lists. (The book is currently out of print, but you may be able to find it through interlibrary loan or used-book services.)
DISCLAIMER: Catholic Answers has turned over the archive to Catholic-Questions.org and no longer owns, manages, or moderates the forums. For additional apologetics resources please visit www.catholic.com.
