I claim the ornamental design for a stackable container with double top handle, as shown and described.
FIG. 1 is a perspective view from the top of a stackable container with double top handle;
FIG. 2 is a perspective view from the bottom of the stackable container with double top handle;
FIG. 3 is a front elevation view of the stackable container with double top handle of FIG. 1;
FIG. 4 is a side elevation view of one side of the stackable container with double top handle of FIG. 1;
FIG. 5 is a side elevation view of the other side of the stackable container with double top handle of FIG. 1;
FIG. 6 is a top plan view of the stackable container with double top handle of FIG. 1;
FIG. 7 is a bottom plan view of the stackable container with double top handle of FIG. 1; and,
FIG. 8 is a rear elevation view of the stackable container with double top handle of FIG. 1.
The dashed lines, the areas within them, and the unshaded areas bounded by broken lines and solid lines depict portions of the stackable container with double top handle that form no part of the claimed design.