The ornamental design for a combinationcoaster and displaycase, as shown and described.
FIG. 1 is an isometric view of a combination coaster and display case showing my new design;
FIG. 2 is a front view of the combination coaster and display case of FIG. 1, identical to a rear view;
FIG. 3 is a right-side view of the combination coaster and display case of FIG. 1, identical to a left-side view;
FIG. 4 is a plan view of the combination coaster and display case of FIG. 1;
FIG. 5 is a bottom plan view of the combination coaster and display case of FIG. 1; and,
FIG. 6 is an exploded view of the combination coaster and display case of FIG. 1, illustrating one or more inserts of varying thickness used within.
Those portions of the figures that are presented in broken lines merely illustrate the environment of the design and are not part of the claimed design.