When I broke my left index finger tip I had a proper stack-splint during the first 4 week. After that I found that the movement of the front finger joint was unnecessarily blocked by the stack-splint. In order to be able to train the flexibility of my finger during the day while keeping it protected at the same time, this finger splint helped me for the next 2 weeks.

The diameter of my finger tip is approx. 18mm horizontally and 15,5mm vertically.

You can try to scale the model accordingly.