5k brass would be pushing it. "if it fits, it ships" only goes so far. They wont ship distorted boxes you have duct-taped into a soccerball.
5k loaded rounds wouldn't fit, and would be irrelevant, as you couldn't ship it anyway.
If you want what will ship in "x" box as brass, talk to YANKEE2500- you can find him in the for sale section, under reloading components and gear.