Horse saddle not fitting anymore?

I have a 14 year old QH gelding who I do Eventing with. His saddle does not fit as well anymore because I broke my ankle and hip and he was worked and un-worked and then worked again. So he gained and lost muscle. The saddle has become slightly too wide and is pinching his shoulders and is low on his withers. The saddle fitter told me to get a half pad. Does anyone know of a cheap half pad that helps distribute pressure that will work for a jumping and dressage saddle? Preferably under 100 bucks. Thanks!