See if this works with your machine
The Janome Screwdriver is designed to remove the Needleplate easily when you want to gain access to broken needles, threads, feed dogs, bobbin case and to clean out the lint from your machine. Approximately 2 1/4" in length.
Part Number: 647803004
Alternate Numbers: 366413003, 820833006
Guaranteed to fit because it is a part.