If you have an exceptional single six with a good trigger job, Bomar/Lansing sights and the right ammo, you can compete quite well in Hunter Pistol class. I have never shot one scoped. I have a 9.5" barrel and shot it until I got an FA. My shooting partner still shoots his single six and beats me most of the time. (but he about out of his ammo stash...).
For scoped hunter pistol, you cant beat the Ruger Mark II with a scope. If you use a B-Square mount, you can even leave your sights on it and shoot both open sight and scoped class. If you are a good shot, you will be competitive.
You don't always have to have the high $$ guns to win (but a lot of times it helps). An exceptional lady shooter was using a Contender in 7TCU with a scope on it and beat all of us guys with our high dollar bolt action guns at a match a couple of years ago. She won handily. It may have been the same match and a guy with a scoped Savage striker ($169) bolt action pistol beat out the contenders, Anschutz, etc.
Get a single six, have a good trigger job done to it, and find some accurate ammo (CCI green tag, Winchester T22, PMC Zapper, Wolf Match Target, Eley Pistol Match) Do a little practice and you will have a BLAST....ESPECIALLY when your scores become higher than the $300-$1500 guns!!
Have fun.....
Steve