With her withers and back shape, I'd look at a used Passier. They have cut
Back pommels and a more rounded shape to the pannels. Whatever you get,
Be sure it's wool flocked, so you can have it customized if need be.
My TB has the same exactly shape. Same exact.
I have gone through allot of saddles. Many bridged, or caused pockets.
The thing is with many saddles that are sold on the market, are cookie cutter shaped. They are all made with the intention to fit the withers, not the back.
"ok, well if the pommel is the right size, so is the saddle" and that is incorrect.
DO NOT BUY A SADDLE WITHOUT PROFESSIONAL ASSESMENT Plllleaase - for your horses sake.
Make sure the saddle rides the ribs, not the spine - the pannels need to be wide enough to beable to dispurse your bodies weight evenly over your horses back...not all compressed near the spine.
Make sure the pannels are spread apart enough - you should beable to fit 4 fingers inbetween the space between your pannels. That means the saddle is riding the ribs - not the spine.
If you cannot......then the saddle is riding the spine.
Really learn how to read the sweat marks on your saddle pad. That will tell you exactly what is going on. Bridging, if the saddle is even. Spine clearance, pockets, distributing the weight where it should be......