It sure looks good for it's age. Congrats on the family keeping it and taking care of the '73. The 1873 vs 1876 are hard to tell apart, but when I looked at the carrier block it looked short for a '76, but the side plates made me thing they were longer so thought '76.Hi Ken. It's actually an original/ authentic 1873 Winchester. It was purchased new in 1876 by my grandpa's great grandfather and has been kept in my family since.
Thanks for the comment.