Varmint; I take it that you live in Californ-I-A. I.m sure there is plenty of Saturday action nearby. (I'm guessing,'cause I live about 1,000 miles North of you!)
If you want to portray, accurately, the goldrush era, why don't you start with an 1851 Navy revolver? If you want to stay with cartridges, and still stay "historical", go to a conversion. The most popular is the Remington New Model Army, using an R&D conversion cylinder (or Kirst).
If you want absolute simplicity and reliability, go for the RUGER New Vaquero in .38/357 or .45 Long Colt. Everybody needs a Ruger, cause they almost never break down or wear out. You will always find it useful as a practise revolver, or for practical carry on wilderness trips.
Welcome to Cowboy Action Shooting!
P.S; The only revolver I recommend without reservation, is the RUGER. For anything else, attend a CAS club and watch & listen. Only after you have decided where you want to go, decide on your battery. In my opinion, every shooter NEEDS a Ruger. The only two reasons to sell one are; You are bankrupt, or you have found another Ruger that suits you better!