www.925-1000.com

Someone on reddit already found: the mark seems to be from Professor Herbert Zeitner, a prominent silversmith of the third Reich: https://www.alamy.com/stock-photo/profe ... itner.html

Assuming German because the crest on top matches Hermann Göring's coat of arms, but it could be from anywhere, I have no idea. I'm actually hoping to do somewhat of a reverse search: maybe the mark on the brush can give me hints of where and when this was made, which could help assess the authentici...