Something I learned recently is the gaited saddles remain high priced even for used. I recently spent weeks trying to locate a used one that would fit a wide horse. Finally an endurance turned up, western style but no horn, in leather/ cordura. At this point I was glad to have found something. From all my searching I doubt you will find one in your price range and may have to be prepared to spend a little more. The name of my saddle tree is the Tennessean. If you check National Bridle shop it will give you an idea of what is out there. Your horse may not need a gaited saddle, it just happened that the width of mine (low withered broad backed) offered a wide enough tree. If he was ridden english I'd have been looking for something to fit a saddlebred or warmblood.