site translates to english and a few cities : Dusseldorf , Koln/Cologne and Heiligenhaus (Rhein-Ruhr)have shops to visit. One can shop online but delivery is not always in a few days.
they have the new Frau Holle Van Gogh water color set. See www.boesner.com
Even if site is only german, few basic words one can look at supplies.
Farben = colors. Pinsel = brush. Aquarell = watercolor. Papiere = paper.
Use search box for brand name.
Schmincke Horadam cadmium red watercolor half pan is 5.89 euro = usd 6.30. CP supplies like Faber Castell the red metal tins coloring pencils are affordable price and better quality than the usual aimed at kids level.
Youtube has some haul videos of art supplies bought at german shops.
Brand Marabu has lots of good paints and mixed media supplies.