This is the German parody forgery of the 1937 Great Britain 1 1/2 pence Coronation stamp.
Changes to the design include Stalin in place of Queen Elizabeth, and “S.S.S.R. Britannia / Teheran 28.11.1943” in place of “Postage Revenue / 12 May 1937”. The text “G E R” has also been replaced with “S S S R”.
The Star of David and hammer and sickle also appear throughout the design.
For more on this issue, see Propaganda and Espionage Philately, by SGM Herbert A. Friedman (Ret.).