I think it's very sweet, and not inappropriate at all...I'm sure your friend will really appreciate that you're showing interest and supporting that she's a part of Gamma Phi
You're a good friend! Hmm...gift idea...I saw a really cute lamp at Target the other day, it's blue rice paper material and it's shaped like a crescent moon. It's adorable! Something like that might be good, I always like getting stuff to decorate my room.