[Lugers down under]

Hello Guys.
Last weekend I picked up a really nice Luger mag pouch at a gun show in Christchurch in our snow covered south Island.

The pouch is very dark brown and I have been able to decipher the maker as,

MARTIN MAYER
MAINZ
1915 or possibly 1913?
I cannot find any reference to this maker in any of my Luger books.
The pouch which is in pristeen condition came with two lovely early mags but not matching numbers.

It has a brass fixing stud and belt type loop on the rear.
I cannot find any other marks .

Any ideas.

Regards
Murray.