Hi David,
Sorry for the late reply. I do hold the rights to the image, and the copies found on free clip art sites are not licensed/authorized by me. While I don't mind personal use I'm sorry to say that I'm not interested in selling/licensing the rights for commercial use to this image as it is of personal value to me.
Nonetheless, thank you for taking the time to track down the original source and asking first!
Also, as I just suggested to rphilmacrac, I encourage you to support wolfsouled and commission your own piece from her!