Replacement nibs (tips) for chuwi hipen h7

I’m looking for spare replacement nibs (tips) for chuwi hipen h7, that I use with my Chuwi Ubook Pro. I’m quite happy with both appliances, that I often pair with a fantastic Huion graphic tablet.

I used my first tip, I’m using the second one that was in the package, but I would like to buy some more nibs for my future work.
Thank you.