I've shipped a small Janome, and had a couple of machines shipped to me. The smaller one was about $20, larger up to $30. Those were USPS prices, though - generally, for larger/heavier packages, you can get better pricing through UPS.
As long as you have the original packaging, I think you'd be able to get it to her for less than what a new one will cost. How kind of you to share with a friend, it's a great idea as since you said, who knows if she will end up liking sewing or not.