Two unusually constructed Scabbards from Afghanistan
 

Here are two scabbards, one for a dagger and one for a sword, that have an have a very unusual manner of construction. My guess is that these are modern repairs, as brass strips are inserted into the chape, which then wrap around the (I’m assuming split) parts of the wood scabbard. Also that is not black leather covering the scabbards, but rather a black Lacquer or tar like substance, which I’m assuming was replacement for the long lost leather.

I had originally thought that these scabbards were of totally modern construction but a sword merchant who sells to the odd tourist could probably just fashion a simple leather covered wooden scabbed without having to resort to this somewhat time consuming and unusual technique.

So my best guess is that these were split, derelict scabbards that had lost their leather coverings, and were repaired by antique dealers using this specific technique, though I could be wrong

I think this is the most reasonable explanation.

Your explanation is probably correct.
With the observation that the chape of the second scabbard is of typical European origin, maybe from the scabbard of an European sword.

Take look at winged hussars swords, in year 1500 scabards were mounted with that kind of reinforcemdnt, this may be copying of that style, or could be older.

That form of reinforcement is also seen on Tibetan swords.