http://www.pdfsam.org/

A new package have been added to the linamh overaly

PDF Split and Merge enhanced (app-text/pdfsam)

PDF Split and Merge is a very simple, easy to use, free, open source utility to split and merge pdf files. It’s released in two versions: basic and enhanced. Includes a console and a GUI interface.

happy using
Mario

p.s.: saving the settings is not possible at the moment (upstream bug: pdfsam not using HOME)