I have a 6 yr old QH mare, and she is long backed. I have a 15.5” Charmayne James saddle now that is so nice, but it rocks on her lumbar area a bit, it rocks side to side more that I would like. So... any suggestions? Billy Cook, Cutsom Racnch RS Saddlery, Josey, etc. I don’t know a whole lot about this area, so lots of info from barrel racers would be great!! Thanks!!!