I never used and didn't like the Eureka Mignon's hopper gate, so I removed it right away. Just to find out that the resulting hole is big enough to scatter ground coffee all over the place.

This print fits snugly around the hoppers throat and plugs the slot.

Fits every Eureka Mignon Model (Silencio, Specialita, Perfetto, Design, Manuale, Classico, Filtro, Crono and Brew Pro)

Notes: 

Some material as flexible as PETG is advisable.