Where to Buy Keycaps
Max Keyboard Universal Cherry Translucent keycaps set
You can find more at
Artistic 3D Keycaps
Artistic Keycap Gallery 2
The artistic 3D ones are typically custom crafted, not mass produced.
They can be expensive, $30 per keycap or more.
You can also find them on ebay, massdrop, or via keycap trade from reddit or geekhack.
If you have a question, put $5 at patreon and message me.