Bullets of .333" are outdated and hard to find.
: Best to go with one of the modern wildcats that duplicates the ballistics, like the .338/06 standard or improved. Lots of bullets and easy brass. A-Square made the .338/06 a SAMMI 'factory' round a few years ago.
: If you want a bigger .338 case & more power, there's the .338 Mag - nums.
: The .375/06IMP is also a great round, ballistics superior to the .333 & .338/06IMP, easy to load at all levels with easy brass and bullets in all weights. .375 is also the minimum for many countries in Africa. It will duplicate original factory .375H&H ammo from 1912.