Here is my 82' and I have to correct myself, it is a large date too. I haven't weighed it yet to know for sure if it is copper or zinc. These are an example of the split serifs I've learned to look for. Could be stronger for sure but you get the idea.
Yours looks more doubled die than mine does. Mine looks more like machine doubling compared to yours.
That "GOD" and date on yours keeps me wondering. If the lighting and focus was better, who knows. I know you are limited on equipment at the moment but shoot, a cheap laptop and usb microscope would make your searching easier. Edit: And the "IN" on the one you posted as an attachment hmmm. Like I said, I'd hold on to it until you can get verification.
I now have the laptop and the camera. But the camera does not work good. I can't complain because it was free, but it still does not do the Job.