You probably will be looking much newer than this, but I believe they won’t adjust older saddles with Hennig trees due to the possibility of damage. I had a Schleese Pouvoir (jump saddle) that was my unicorn - fit my gigantic withered TB with no additional half pads, shims, nada thanks to the flair panels. And it was a joy to ride in. But I have also ridden in several older dressage saddles that I found lackluster (the 2x4 seat mentioned above!). I haven’t sat in anything made in the last 10 years for sure.
Also, I’m happy to hear that I’m not the only one who doesn’t have a $6k saddle budget