1870s

Howdy, I found this little thing all bent up at an 1870s house. It reads "5 Burnett" on one side and the back is blank. A little bit of searching on google and a token website produced nothing but I think one of you guys will probably recognize it. Any thoughts or opinions are appreciated!

I got out today for about two hours at an 1870s house near me (same place where I got flying eagle, chinese coin, gold earring, and a bunch of other stuff) and I did a little more research and it was apparently also the site of an 1850s/60s post office, neat. So I went back today and dug for a...