Are the actions a s/a .473 bf and l/a .535 bf?
Like I already said, there’s nothing wrong at all with the two plans and I’d start with the 264 WM build of it was me
I’m all about firearm Lego’s though and I have my own plans for a few bolt actions I have access to(one is mine, one is my father’s). There’s no reason to limit yourself to one cartridge per action, unless these two guns are just two more in a big collection . It’s easy enough to select remage barrels or get an action blueprinted and have the measurements saved. Then you can select from any of several combinations that suit any scenario you nee