I hunt deer and boar with a Freedom Arms 83 in .454 Casull. My current model is iron-sighted and has a 7.5-inch barrel. I agree with those who suggest a 4X scope is too much magnification. I once used the same basic model with a 2X Leupold scope mounted, and it provided sufficient magnification.
One suggestion: do not skimp on the scope and mounts. The .454 can be a hard-kicking round, especially with the lighter weight factory loads. The scope and rings have to handle that recoil and torque, and the scope and rings on a handgun are a much higher percentage of the total weight of the firearm system than a scope and rings on a rifle. Just like bullet pull is an issue with really light revolvers, scope damage and mount battering can be an issue on the .454. So when you choose a scope, look at warranty and customer service.
You might also consider loading down or running hot .45 Colt loads as you may not need full-throttle .454 loads all of the time. I like to load my .454 with 300-grain bullets at 1200 fps for deer and boar but I used different bullets for the different animals.
Another suggestion: If you like single-action revolvers, look for a used FA 83. There are great deals available, and the FA 83 was designed around the .454. It is possibly the finest revolver ever made, and they can be found very lightly used for not much more than a new Ruger.