That is about 2.6cubes before your sub displacements. Did you want to use the same box or are you willing to build or buy a custom one? Can you allow any more room on those dimensions or is 15'' the tallest you'll go, 10'' and 5'' the deepest you'll go?
If you are willing to do 50''x15''x7''x12'' with sufficient bracing you'll have enough enclosure volume to fit two 10s ported with a 6'' aero firing towards one of the corners.