(in Igwilly's voice) And the Complete Barbarian's Handbook.
It may be that they just don't have a physical copy on hand to scan, yet.
I would choose Wrath of the Immortals. I mean, it is an “important” book for BECMI, I guess.
The previously mentioned book is one I would like to have it, but bets aren’t about your wishes.
However, I cannot actually make bets right now. I’ve spent all my available money in fancy wizard-themed RPG dice![]()