If you do a bit of Googling you'll find that Lavender is frequently and fairly easily grown from cuttings. I won't give a link because there are so many sites that will tell you how to do it.

Hi, a good friend of mine gave me a rooted lavender that she propagated from a stem cutting and it worked great for her. She said they done real good. My guess would be just Google, Propagating lavender from cuttings, and see what info you can find.