It's hard making recommendations to someone you don't know, but here goes:
1) First make sure in your own mind that she would welcome a gift like this; that is, be aware of potential subtext. You know how we women love to read into things, so are you sure she would want one? Does it say, "I don't think you can take care of yourself on your own"?
2) As Bexy points out, things like this are extremely personal, and I second her lingerie analogy: it has to be something she feels comfortable and sexy wearing, and not something you think she looks sexy wearing.
3) At the risk of generalizing, penetration is usually not as important as stimulation. Thus, I would second Joan's recommendation.
4) Finally, I suspect what would be sexiest of all for her would be to somehow do it together. I can't speak from personal experience, but I can only imagine how lovely it must be to cyber-skype.