I don't know guys, I bet this guys got a half dozen, rifles that he knows would work fine.
He also sounds like a guy thats cartridge bored. I kind of like the idea of a 1000yd bull gun,to hunt with.
Actually I don't!
Of the following I wouldn't say any are sufficient
223
243
8mm Mauser
7.62x54R (only because it comes out of a POS Nagant)
7.62.39
11x58 Beumont.
If you absolutely have to compromise, I'd go with a 9 pound 308 or '06 with a number 4 weight barrel. The 308 or '06 will kill the largest elk that ever walked at reasonable hunting ranges and won't knock the ears off a brass monkey when you're shooting off a bench. Top it with a 3x9 high quality scope and you're good to go.
That's about what I'm thinking at this point too. Except probably a 4.5 to 14