ruger new vaquero in 45 colt. hands down. they are competition ready right out of the box. cost around 550$ but i HIGHLY recommend spending a few more shekels and getting the ones with the 45acp and 45colt cylinders
i recomend 45 over the 44 because a big fat 45colt is MUCH easier to reload and manipulate unloadings than thin skinny 44mags or 357 mags
everything else you gotta spend MORE money to get them in shape to run cas. so if you buy anything but a pricy colt or a ruger new vaquero you end up spending colt money on a cheap gun.
voice of one who is a current cas shooter GET THE RUGERS!!
get em in stainless easy to clean.
my pair in 45colt with extra 45acp cylinders