Purchased item from a person who was very much into the history of the Kings Park Psychiatric Center. He has recovered many items from former buildings and I asked what was the most disturbing thing he saw. He told me he has recovered many old door locks, but there was one he recovered that could not be open from the inside as it had a steel plate blocking the key hole. It came from a reinforced door from a patient's cell. Scary to think about why this was done and who was in a cell with this tight security. 

I have search the internet looking for a similair lock and have seen none from Kings Park Psychiatic Center with the same type

of cover blocking the Key Hole.

Good Luck ,Thanks for looking