A .300 H&H and a .458 WM+ is for sure a great combo. A pair of 3.6" strokers is good. Mine is the .375 WBY and .458 WM+. My pair of 3.4" strokers would be the .300 WinMag and a .458 WinMag.
3.6 Strokers, i like that Sir Ron, a lot of good choices, 264 and 338 WM hulls are perfect light lifters for the 458 WM+ as well, a lot of good stuff from Ma Winchester in that era.