Not to take business waway from anybody else, but do a search for the Proscale LC-50 from Old Will Knott Scales.
Mine was $32 shipped, uses 2 AA Batteries, weighs absolutely dead accurate. checked via a huge host of Lab Reference Weights. weighs up to 50g, with .01 resolution, and is, as far as I can determine, it is the exact same scale as the $225-$250 Clearaudio Weight Watcher Scale (minus the little weighing ledge, and of course, Clearaudio's name on it)
One can make a ledge if necessary from a non-magnetic material. or just set the Scale on a deck of Cards, and set alongside the Platter. Mark