I'd guess it could be done with a 6.5PRC and a 123 Absolute Hammer. They fly out of a 260rem, and recoil is manageable, so calling your own shots is doable.
No advice to give, but I feel your pain having previously been financially tied to a family member. Greatest day ever when I finally was able to close that chapter of my life.
Its a little OCD, especially if you intend to hand load for the gun, but I don't see a downside other than cost. Really, the chrono and your groups at a set distance will probably be the only benchmarking you'll really need.
I've been wearing Walker Razor electronic muffs in the goose blind. If there is a lot of activity I keep them over my ears and the sound up. If its quiet I keep them on my head and my ears uncovered so I can talk with my friends.
I never even considered this, concerning backpacking meals. But I did read a story about a guy that brought McMuffins into Australia and got a big fine, so I could see it being a problem.
I found an interesting conversation here: http://www.outdoorsmenforum.ca/showthread.php?t=208810
Looks like a Model 7 stock might be close? Manners made me a really nice Model 7 stock not too long ago.
Its hard to beat Grendel, 6arc is almost too close, but I think its a little better overall. The new 22arc has me thinking about converting one my 6arcs over.