Just the front panel of a 16th C CE Italian Cassone (chest), now in the collection of the Minneapolis Institute of Art.
The animals on the panel aren't actually sea-horses or hippocampus(es), because they have wings - please let us know in the comments if you know what they're properly called.
A little more information about the object here:
https://collections.artsmia.org/art/542/cassone-italy
If you want to print the panel or carve it on your CNC, let us know and we'll make a higher-resolution file.