Looking at the book's cover, it is easy to see that this it is in no way new. The cover looks to be made of an old metal material which has rusted along a couple of corners. There is no writing on it, however, there is a large, silver raised symbol in the center. It is the same symbol as the pendant had on it.
As for the tapestries, there seems to be one for each of the major Deities, organized haphazardly and obviously not by priests of the said powers. If priests had done it, it was unlikely that Correllon and Gruumsh would have their symbols next to each other, and all the tapestries on the whole look wrinkled and even dirty in a few spots.