Field set/kit for Artillery plotting(152mm M1937)?

[tusig1156]

Can anyone give me more information as to maybe the country of manufacture for this piece? It appears to be some sort of a Plotting set for field use for a 152mm M1937 artillery unit. Only issue is I can't figure out what country manufactured it. The instructions are in english but I don't know of a country that adapted the M1937 that would have made the instructions in English. The story behind this is that it was brought back from either Iraq or Afghanistan and was found in a bunker. As you can see it has a backpack built into it to carry it in the field. The on the data plate pictured it has the letters "G-H" which look familiar but I can't remember where I've seen those letters on something. I know the finnish sometimes use the "GH" designation for "gun howitzer" and since the Finn's used a small number of these guns, maybe its Finnish? Still doesn't explain how it got to either Afghanistan or Iraq but the wiki article on this gun did say it was seen being used by the Northern Alliance in Afghanistan and probably some were sold to the Najibullah regime(before Taliban). Maybe those came from the Finns? Would the Finns have made some plotting tables in English? The font of the words on the instruction plate also might look familiar.

The same guy I bought this from also has an unused Vietman War era USGI P190 mine detector set that was also found in the same bunker as this plotter. There are some arabic letters painted on the outside of this mine set so this seems to lead credence to the story on both these items. Haven't decided if I want to buy it or not but I thought I'd include this info to maybe help with the Plotting set ID.

Pictures:

 

[tusig1156]