Nice one. I've only come across one of these in all my searches. As for value, I recommend checking recent ebay auctions to see what the average sale price is.
Definitely a real double die. Congrats! The value of a 1971 penny DDO is about $1,079 in mint condition! By the look of the photo, the value should be somewhere between $700 to $800. Something you wanna keep in collection or sell?
Very late die state . I'd give it a brown in color . 58 in grade . make it worth 140.00 . https://www.pcgs.com/coinfacts/coin/1971-1c-ddo-fs-101-031-bn/38007
