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