Does your GF get a say in this?
Seriously tho', it depends on what you like about the fragrance. If it's the oriental/vanilla thing, then try these:
Shalimar Ode à la Vanille by Guerlain
Eau de Shalimar by Guerlain
Vanille Noire by Yves Rocher
Orchidée Vanille by Van Cleef & Arpels
Dior Addict by Dior