(Not to be confused with this question.)
I recently moved, and all my Klafim got mixed up. I have some for Mezuzoth, some for Tefillin, and some for Sifrei Torah. It just so happens that I was writing Sifrei Torah for pixies (there is a tribe in the Amazon rainforest that considers itself one of the lost tribes and intends to be converted by the Israeli Chief Rabbinate after they are brought to Israel), so I'm using Klafim about the same size as my Mezuzoth and Tefillin.
Is there any reason to assume one size is Muktzah over the other or to assume a more expensive klaf is Muktzah over a less expensive one? Also, since I'm the Sofer, I'll be the final seller, so should I use my cost or my sales price to determine the value (if it's relevant)? Is every Klaf Muktzah? Would it only be Muktzah once it's been assigned a use (or would it only be non-Muktzah once it's been assigned a use)?
How can I identify which of my Klafim are Muktzah and which are not?