This Paul Wirt countertop store display case was featured in a 1908 catalog ad, pictured below, and sold with an assortment of Wirt pens. My cases are both missing the arms on the sides that allow it to stand up tilted back. The first is top loading, and features a pin in the back that locks into a ring at the bottom of the inner portion of the case. The second features a tilt away front.
This second case is similar, but this model has a front that tilts open to access the pens.