Identifying a spencer New Model carbine

[TheFrenchGunsmith]

Here's a good one, I bought this spencer from an old man in France, the story goes that it belongs to his ancestor, who fought during the Franco prussian War. And it makes sense, France bought 5000 spencer New model carbines from Winchester. But there are a few problems :

From the buttplate to the reciever, it is a spencer sporting rifle (it even has the two screws for a diopter, and the outstanding walnut stock). With a serial number errased - - - 986. Which matchs every part.

But the barrel and forstock are standard for a military model and marked NM (short for New model). And it does have the standard military front and rearsight.

What I believe this is, is a bit complicated. France bought those 5000 carbines from Winchester. This carbine has been renumbered to 1259 (which is in the 5000 range), numbered on the barrel and the inside of the stock (I garantee you that this number was added a long time ago, because it has not been disassembled in more than 50 years). So, when Winchester bought Spencer, they had a lot of parts left (including sporting recievers). When France ordered the 5000 spencer New model carbines they did not make 5000 new ones. They reused recievers, and stock to save cost (and because both the sporting stock and the NM barrel are marked 1259 I believe this is all original and not a Frankenstein spencer !).

Let me know what you think !

Here is a link to all the photos (reddit thread) https://www.reddit.com/r/ForgottenWeapons/s/9paX56XCDo