I can’t confirm that any deliver sub-meter accuracy. The Surveyor is Bad Elf’s best option in terms of their Bluetooth GPS receivers which delivers ~1-meter positioning. Of the Garmin devices that I’m aware of, none of them advertise sub-meter accuracy. I recommend reaching out to Garmin with your inquiry as they can provide a more thorough response.
Please let me know if I can assist you further.
All the best,
Avenza Systems Inc.