Im not sure with Fimo you can get thin enough sheets to represent scrolls. I would likely try heating and bending some plasticard (sheet styrene). I would also suggest you start with plasticard as the book cover and binding for your scribe so it is perfect, then sculpt the pages and such.
Not having a good hobby/train store near me I picked up some sheet styrene recently in the form of a 'for sale by owner' sign at the local hardware store. works the same!
I do most of my sculpting with green stuff, unless its a weapon or something I want very hard with sharp edges, then I use a two part epoxy from the hardware store meant for fixing ceramics or pipes or something.. drys like a rock in like 15 minutes and can be carved with an xacto or sanded with sand paper/dremel.