You also need serial.device in Devs:
Yes, these are files you can copy from the Workbench 1.3 floppy disk.
The "show all files" menu item was introduced only in WB 2.0. Actually Workbench was never meant as a file explorer. You should think of it as a kind of start menu.
To look at files you can use disk managers like CLI-Mate or DosControl. I think there is even a version of Directory Opus which works on Kick 1.3.
