Going to have to stick to the Sig556 platform. Can't get replacement parts for it now, but I still love this platform. Pistol would have to go with the Beretta 92. Reliable, feeds any ammo I give it, good mag capacity, and accurate.
You didn't say it had to be a black rifle..
.44 Mag Lever action / .44 Ruger GP100
I actually have levers and revolvers ready to go but all in .38/.357.
Were I to do it over, I'd go with .44 Mag / Special.
The Ruger is a no-brainer.
I would have to think about the lever gun. probably a custom from Wild West. Wild West Guns
Make room for a new boner