Salve, Frakka!
I will recommend a good film and foil capacitor. Solen in France seems to make 2 lines of film and foil capacitors. You should be able to get them easily. I normally do not care for the sound of metalized film capacitors, they sound brittle, or have a metallic edge to their sound, but they are inexpensive. Film and foil capacitors have become more expensive over the last 5, or so, years, but they are worth the cost.
Your dust looks just like my dust!! 😆