Very few horses need a wide tree.
MBP, let me disagree here. It depends on brand/model of the saddle. Say, all jumping MTs I tried were too narrow for my paint (even though she's rather TB-type), however Thornhill (both - jumping and dressage) medium was just right.
OP, Classic Saddlery has -new- MTs on sale from time to time that would fall in your price range. I've also seen Pessoas in an excellent condition in that range (although I'm not a fan of it personally).
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