The sort of box that tea was shipped in from india etc, is a plyboard box, typically three-ply, with metal strapping down the edges. Inside, it was lined with aluminium foil.
They used to be quite commonly available over here (australia). Looking at the samples on e-bay australia, there were boxes with 40 kg, 48 kg, 50 kg, and 58 kg net, the tare was in the order of 5.3 to 10 kg. The typical quoted dimensions is 40 × 40 × 60, or sometimes 50 x 50 x 75, or around 3 to 5 bushels. One site suggested six to the metre, which might suggest the latter is a typical size. In any case, these suggest a shipping density for tea is in the order of 1/2 of water.
The correct google-search is "vintage tea chests" "bushells tea chest" also works.