Here a new idea that popped on my head.

The design uses an external windmill to turn an internal camshaft, transforming the rotational movement into vertical displacement that simulates the motion of waves. I added a scaled down a benchy to the diorama, I'm looking forward for your ideas to add at it!

Assembly is easy, here is a GIF of the model disposition, and a reel of the full assembly:
[https://www.instagram.com/reel/DXm1XRPDDPx/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==](https://www.instagram.com/reel/DXm1XRPDDPx/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==)

The diorama comes with tips to make them easily fit to glue on. The thread at the bottom is able to hold the box in place. The pole version of the thread is to be able to fix the automata to a stick.
 

I hope you like it!