Here are images of a genuine 1871 half from a Heritage auction. This coin was graded AU details, cleaned by ANACS. The poster's coin seems like a close match in terms of design features, so I'd say it's likely genuine. Stumpy, you should check the weight (it should be very close to 12.4 grams). If it is significantly lighter you can be confident it is a fake.
Assuming it's real, that's a remarkable find, even cooler than the occasional Barber half finds reported on the forum. I'd grade it VF-30 for details. With the scratches and corrosion spots it should be net-graded down to the F-12 price level or so. You could probably get $50 or so on
ebay, maybe a bit more. Congrats!

