Luger magazine markings question

[admiral1960]

Hi all,

i have a Luger magazine that I am trying to figure out who made it and when.

The only markings are on the aluminum base.

The markings are:

1. the serial number (8311)

2. a lower case h below the SN

3. a plus sign below the h

4. below the h an eagle with 83 below it. The eagle and 83 are very small.

The body is steel, blued

Thoughts please !!