Let me start buy stating what I know (very little) & what I do not know (a lot) about these items.....
I have no idea how these plaques were awarded, (if they are indeed awards or just commemorative plaques), whether they were given to all the fighters & their support/seconds etc or just the fighters themselves. I do not even know whether they were given to both sides or only the winners???
What I do know is that they are tough to find, which could be to do with how many were given out, or because they appeal to not only TR collectors like us, but also sport/boxing collectors. They were NOT given in presentation cases, just in a simple paper bag with the manufacturers details (which is Aurich, I'll show one later), so if you find one in a box or case, then they have been put together at some point, either by a previous owner or an unscrupulous seller....
Programs & postcards/envelopes with special cancellations exist for the fights, however, while I have seen images of the programs, I have never managed to find any for sale.... The postcards/envelopes can be found on various Philately types sites.
There are also a small number of badges available, as rare as the plaques, if not rarer. I assume that there were badges for all the fights where plaques were awarded, however I have only seen ones for a couple of them. I will cover them in more detail later....
From the ones that I have seen, the plaques come in three colours; Red enamel for the Amateur Box-Meisterschaften, White enamel for international bouts, Blue enamel for Box-Landerkampf before mid 1941, & Black painted for late 1941 onwards. Plus there is a totally different painted design for the "Kriegs-Europa Meisterschaften im Boxen 1942". Except for this last one, all of the plaques are 8cm/3inches in diameter.
So, to start Amateur Box-Meisterschaften.
I Know of three: Essen 1939, Stettin - Königsberg 1940, Görlitz-Breslau-Liegnitz 1941.
I do not yet have the Essen, hopefully Bill will be kind enough to show his one. I can tell you that the Essen fight was staged 21st & 22nd March at Städt Saalbau & 24th & 25th March 1939 at Kunsteisbahn Essen. However I do have one of the badges. As you can see, they are the same as the palques, but not enamelled. They measure 3.5cm/1.5 inches.
Stettin - Königsberg 1940. I've no idea when the fight took place; To save space I will only show one reverse as they are all pretty much the same.