I know, there are a lot of book holders, but most of them helps keep a book open with one hand. When you for example play a guitar or eat :) you still need one hand more.
I play a guitar and it makes me crazy when in a middle of the song the book closes itself.
So - no more.
Print base 1 or base 2 - whatever you like and 2 x holder (flat part down). No support, no raft, 10% infill, just print and use.