After looking at a few other Kin grinder funnels, I didn't see one for a K1, so I decided to make a new one. My original larger one (100mm Diameter) kept getting knocked off if I wasn't precise with the beans, so I redesigned it with a double-ring design that slips over the top edge.
At 100mm in diameter it felt a little bit oversized as well and so I ended up making a slightly lower, 80mm diameter funnel that had 10mm lower rise. Both files are available.
The author marked this model as their own original creation.