Excellent story, put a big smile on my face. Just try my trick:
Put paper in other boxes, so no spy really finds out that there is Agfa in the Ilford box, use relabelled stuff like Classic or private label stuff, only few people know that Photo Reinhardt Film is actually A..a, packed by T..a, as they had to close most of their shops, there only very very few left.(I mean Film stock as well as knowing people).
Decorate your darkroom with lots of stuff you would not even consider using, like Kodak Farbwelt colour film, once they find out, they close out these products and the world will be a better place!
Consider using Foma Products, at Photokina they were quite positiv about someone travelling to Prague to buy stuff at their downtown store. (The price is about the same as in regular stores in prague.)
Good luck for your supplies,
Wolfram