I bought a strong tote [flip top with interlocking lid] and filled it with foam padding, and put some thin plywood layers in between foam layers. Glued the foam to the plywood, so that it wouldn't slide off when I took the layers out of the tote.
I have a Vendetta / tank level, another tank / sentinel level, and an infantry tray on top. Worked out well, and only cost about $40 to make.