Alpha Epsilon Phi national policy stipulates that no one other than initiated sisters may wear or use the Greek letters. New members and non-members may wear items that read "AEPhi" or "Alpha Epsilon Phi" spelled out, but only initiated sisters may use the letters AEΦ.
Our new member pin is the crest, with the Greek letters at the tops of the columns removed, so there's no prohibition on the crest as long as it is modified so the Greek letters (particularly the Φ) are absent.
Needless to say, letters are a popular initiation gift.