I just had an idea on how to create a smaller icon. It is a little cumbersome for every purpose but some might find it useful.
create a notebook just to store your files you want to have reference to in other notes (a file storage notebook)
Inside the file storage notebook, create a Note for each file you want to link to and put your file there, naming it accordingly
Grab the "Note Link" (right click on note you have created and "Copy Link Note")
Paste that Note Link where you want to reference that file
This will create a link to where you stored your file, with the note title as the link to the file you want to refer.
Hope you find this useful for special use cases.