Allied booty of German weapons and ammunition after 1945

I am helping a friend with a book project. For this we are looking for documents which are stating on possible booty weapons and ammunition and how or if they were shared amongst the Allies after 1945.
Of interest are all quotable sources. In case somebody knows any document or publication on this subject it would be highly appreciated to be pointed to such documents.

There is the book “Veteran Bring Backs” about guns, ammo, and things brought back from Germany and Japan by U.S. troops. There is a volume 1 (Germany) & vol 2 (Japan) , and this link is volume 1 (scroll down to see vol. 2):

In the Bundesarchiv-Militärarchiv there are files on early Bundeswehr MG42 procurements, which should include buying them back from France (and Norway, I think). Maybe these are of interest to your friend. I did not see these files myself, but you can find them by searching on the Bundesarchiv website.

Some time ago I read a story from a German expert who worked for the French after 1945 and told how the French tried their very best to prevent the British from learning what the German experts knew on hollow charges. I will look for the document.

Your friend is working on a quite touchy subject.

Matt, JPeelen, I am after the official regulations for what governments did not what soldiers took home. Also Germany buying back is secondary here as I need to ID the step before what means on which basis captured German material was distributed amongst the Allies. There must have been an agreement or treaty between these countries.

The focus here is on weapons and ammunition in caliber 20x138B Rheinmetall.