I just wanted to point out something to this reader. Old sidesaddles are usually quite narrow because that was the typical body type of the Victorian era horse. Newer sidesaddles however are designed for wider bodied horses - all the way up to drafty's! Do not give up on your dream just because you have a larger breed horse. I have found quite a few pictures of ladies riding draft horses and other large breeds.
Go to my sidebar where I have internet stores and sights listed. A couple of them are very reputable sidesaddle dealers and I know one specializes in Elodian sidesaddles - (Hundred Oaks) which are the ones made for larger breeds!