I would think a 375 H&H would be more verstile in Alaska.

Personally I agree totally with your approach for an Alaskan bolt but would use a different action like a granite arms action as others suggested above for a custom project.

Short of that and being tight with the dollar I would look at the new 375 Alaskan in 375 Ruger and replace the trigger with a Timmey trigger.That would give a versatile standard length action rifle that could be used,even abused somewhat, and still get the job done