Wow, what a quick and helpful response, thank you all so much!
The moment this button came out of the ground and I saw that eagle, I knew that it was one of my favourite finds ever. Your information has only hardened that feeling. CannonballGuy, a lightning bolt shot up my spine upon reading your detailed description, thank you so much for that, I might have to call on you again in the future because I do not have any such books. Thank you again!
CRUSADER, I did have a feeling that although the property was inhabited during that time, it was possible that the button was older. I wonder if maybe some veteran American friend of the War came and visited the house, proudly wearing his colours, and lost it along the treeline out front while dismounting or something. I'm not sure, but the whole thing just makes me tingle.
Thanks again!