I found this place on the internet. If anyone knows anything about them, I'm intrigued by their hunt offerings.
Billy Lindsay in Arkansas repairs hunt whips as well as making them. Or at least he used to. He's a true craftsman, from what I gather, as is Eleanor Hartwell who is also an artist to go along with her hunt life.
The best whips in my experience are to get the handle of the whip from David Thorne - http://www.huntingwhips.co.uk and then the thong from http://www.nylonhuntingwhipthongs.com - they do brown or white, and are far better than the leather ones. hope that helps, and Happy Hunting from the Blackmore Vale in Dorset!