Mike,
There is some very good information in this thread.
Since we are spending your progeny's inheritance
why not order a second set of barrels. A set in the 400 NE class say .470,regulated at 50 meters and a 9.3's or .375 Holland regulated at 100 m. Practice with the 9.3 -.375 ........and just enough with the .470 to see where they are shooting.
If a scope is a -necessity- on the .375 Holland : a S & B Zenith 1.1–4 x 24 and claw mounts.
Trust me you will not feel the recoil when the Buff is in your sights and you squeeze the trigger on the .400 NE.
To the best of my knowledge, everywhere in Africa where caliber minimums are enforced the, .375 H&H is the legal minimum.
Wish I had those enviable decisions to ponder.
Good luck with your endeavor.
Good Shooting
T.C.
