Drilled out jumpring is typical for 1813 EK2 Prinzens. It is one of the crucial signs, that particular 1813 Prinzen is period one. From this reason you can see original 1813 Prinzens either with drilled out jumpring, or with jumpring repair (as this style is very fragile).
These prinzens are last in EK 1813 production line, after all serif and sanserif pieces, bent stems and wideframes. They were produced in 1850´s, which is quite close to 1870 era. I am posting some "borrowed" pictures of the second EK2 1870 with this style, which I had seen and missed on ebay before.
Last two pics are of my 1813 Prinzen.