The outfit and hair of the main female character are '60s style and not '40s
Not to mention Franciosa's fancy and expensive 1968 Hollywood haircut. Actors' willingness or unwillingness to have their hair styled appropriately for period films is a good tip-off to how seriously they view the whole project.
The map on the wall during the meeting of the British intelligence (17min26sec) is a post WWII map. Just check the borders of the former Soviet Union, Poland, the former GDR, the former Czechoslovakia and Austria is a different country. If was a truly 1943 map the borders should have been completely different.