Size #3 Flying Eagle Post Office Box Door

The door is approximately 6" x 11", is made of brass or bronze, and is in very nice condition. I have included photos to show that all the working parts are still there but I do not have the combination. With some time, effort and know how you could probably determine the combination. I believe that this door was produced by the Keyless Lock Comapny in the 1920's but I can't positively confirm this. Please e-mail with any questions and thanks for looking!