Fake as hell.
Artificial aging is obvious from the mechanical uniformity of the tear marks.
Discoloration is entirely patterned and grained without a typical repreive of sorts at the spine.
The aging of the language is off for the era.
The ink of the pressed words did not wear in the same fashion as the paper (degradation would be much more pronounced).
Even with the printing presses of the time "print on demand" was not a large concern for publishers, so a small (adult and therefore hard to source to any large companies) custom printing such as this would not exhibit the uniformity of text, especially with the margin similarity of two pages.
Also the artificating of the corner objects is the last huge gaping give away I can identify so far.