You are going in the right direction since you have the rifle first. I went in the wrong direction myself with the pistol then got the rifle, then got into reloading and realized I had a pistol not strong enough for the ammo the rifle did best with. Wound up having to get more .45 pistols, oh the agony.
You don't speak of it, but if you hunt with the .45 Colt rifle sooner or later you will want to reload to improve performance over the anemic factory ammo.
Many of the rifles originally designed to handle 30-30 ammo chamber pressures but sold in .45 Colt variations are far stronger than a Colt SAA. I don't know what the limit is for those rifles, but I note at least one is available in a .454 variant and those can easily reach 100,000 PSI if one uses the original triplex loads.
Elmer Keith lists some .45 Colt loads in his many writings that are excellent loads, but they are way too stiff for the Colt cylinders (which is how he lost a finger when one burst). If you are using a Sharps or a Rolling Block type action the bullet type is of little importance. However, from a lever action you will probably be much happier with a rounded bullet design. In my own Winchester M 94 Trapper Carbine I use Hornady XTP bullets with Keith type 2400 loads. (Loaded up 450 of them, so I should be good for a very long time, possibly running out somewhere around age 98.) They feed as slick as if they were military hardball and at the indicated velocities hit Bambi like an AP grenade out to 100 yards (which is fine as 10 - 30 yards is the most common range around here).
I can't use those loads in any of my Colt products. The original BP chamber pressure was somewhere around 14,000 - 20,000 PSI and I am way, way, past those numbers. I found a website that claims the S&W M25-5 will handle such, and I have one of those, but am dubious about trying a steady diet of such in that gun. I have done a few, but I think it is near maximum for that gun. Since the .45 Colt loads I worked up are near the bottom end of .454 Casull pressures I went with a platform designed for that load. It is a little more weight to carry on my hip, but it gives me 100% ammo interchangeability. I primarily looked at two platforms, the Freedom Arms SAA and the DA Ruger Redhawk series. I did look at the Ruger Blackhawk, and the Vaquero. However I have a friend with a Vaquero and when he swore his Vaquero would take it, I gave him a cylinder full to try out. He reported a very violent recoil and said he only fired two of them and his hand stung for hours. Based on that, I went with a Redhawk as it was less expensive locally than the Freedom Arms Colt looks like. The Redhawk is a beefy pistol and the cartridges for my rifle are almost pleasant to shoot in it. I wouldn't want to run a 60 round PPC course with them two times in one day, but a quick cylinder full or two is no issue. Of course the (laughable) cowboy and normal factory ammo will also shoot in it all day. If I absolutely had to have a Single Action pistol design as my ride along my first choice would be the Freedom Arms pistol with the Ruger Blackhawk coming in as a second choice.
If however you don't and don't foresee reloading then a pistol like the Colt is a viable choice. With that criteria I would pass by on Colt for daily carry as being too needlessly expensive and choose a US Firearms looks like a Colt revolver (made on the old Colt machinery).