David--hi, and welcome to the board. My name is Jay Miller. I am one of the authors of the Old Judge book. Joe Gonsowski, another author, may also jump in later. As previously mentioned, the Shannon card is an 1890 Players League card. These cards are scarce. The card you have posted an image of has nice clarity, which many times is not the case with 1890 cards. If I were going to guess I would say it is probably worth about $2000. If you have further questions you can email me at
oldjudge@gmail.com
Jay