I've included a blank tray that you can use to create your own, or use the infill setting on your slicer.
@bagel has some great examples and details on how to go about it here.
The author remixed this model.

I recreated this from scratch in F360, reducing the size, removing the text inside, altering the tabs that hold the tray so that they don't need supports, smoothed out the corners to make it more organic, added a chamfer to the base to help it print, introduced a drainage hole to prevent it filling with water, and added a few new designs for the trays.