FamilySearch has a free "Disk Doctor" service, that may be able to help (no guarantees.) Send an email to firstname.lastname@example.org Subject: Disk Doctor Attach the files, and explain the situation. What file format do you want the output in?
They have a Mac to run the old Mac PAF 2.3.1 software. (This is database software, not normally used for storing the text of books.) If the files can be read by MacPAF 2.3.1 the data can be exported in gedcom format, readable by current genealogy programs.