They are national, just not part of NPC, though they may be on their campus.
nat'l site
http://www.phibetachi.org/
her chapter in iowa
http://www.stuorg.iastate.edu/pbc/
can you ladies reserve rooms on-campus? are you allowed to get we call them craft rooms, but just a room where you can always meet?
in the winter, do snow stuff.
invite them to do philanthropy with you,
to get your name out, sponsor some speakers/activites (with another org too
) wear your letters, do random propaganda