Regarding the horse shoe. It's for a hind foot, it has a toe grab and heel caulks called "corks." You are in NY where there is ice and snow, so I really don't know, but what they were doing required the horse to have traction, possibly a saddle horse on ice. More likely it was a work animal. You say it was found in the woods so my guess is it might have been skidding logs. The way the one heel is bent down, because it is a rear shoe, it looks to me like they figured they could get away with leaving a little heel sticking out at the back of the hoof, and the horse got it's foot in a spot that the shoe was hung up, and in the resulting wreck the horse pulled the shoe. The nails are soft iron, and will usually rust away, but that doesn't always hold true either. My best guess as to age without getting to look at the shoe more closely, I think toe grabs that were put on the shoe by the horseshoer went away by the late '60's, at least any toe grabs on shoes I did out west were cast onto horse shoes that were a completely different brand and style than yours. In order to tell if the toe grab was added by a blacksmith/shoer with a forge, clean the rust from around the base of the grab, and see if you can see a fine line of brass where it was braised onto the shoe. That would give the shoe a possible date back to the late 60's or before. Otherwise it's near impossible to date horse shoes, and as far as that goes, toe grabs could have been used back east a lot longer than the area of the west I was working, so my date could be all wet.