In my experience, that is the absolute toughest book to find intact, among all the Mad specials.
Other tough ones include the specials with the floppy records (the early ones, like the Worst issue with the Beatles cover), the zeppelin issue, and the mobile (sculpture) issue.
But the full-length Alfred issue is by far the toughest. Imagine how many kids' closet doors and dormitory walls had that poster on them.
This is about the only one from the late 1960s to 1980s, all these are pretty common but some great and classic covers.