While almost every Missouri state highway marker uses one of two versions of the state outline (see here or here for a direct comparison), once in a while you find an oddball marker.
This one (left), photographed in March 2003, was on Missouri 152 just before Missouri 291 in Liberty. The outline attempts to be unusually detailed about the shape of the state's borders, the Bootheel is oddly shrunken, and it's clearly impossible to get the route number centered within the outline.
Another marker, shown in the photo above taken in October 2003, has a directional banner with the unusually narrow font (FWHA Series B). There's also a square version of this marker and outline nearby.