JJ

Not so (coincidence).

I've seen a number of English gun makers books with
identical guns following each other, especially if
they are pretty much standard stock guns and popular
guns of the day.

I think the same would apply to Mauser.

The fact that they had to send one gun out
makes it logical that they send more than one,
especially since they were a retailer and
the likely arrival of one would generate
a sale of the other.

.