I had a Garmin Astro (set up to use to track my dog when we're in the field). I believe it's based on the 60 series. It has measurements in feet. I used it to measure distance on my deer kills last year. It has since gone missing
Most all the Garmins go down to feet. Keep in mind you are getting to the limits of what the technology can do. The nearest 5 yards is probably a better idea of what most GPS's will resolve to.