I got a used Oahus JR 300 on eBay for $6.50, plus $10 postage. (From "Qwik Pawn" in Montgomery, AL.) Targeted at the jewelry/gold market (does troy ounces in one mode), but it also does grams. I presume gold buyers would not want an inaccurate scale. Range is 0-300 grams.
I do need to get a 200 gram weight to calibrate it.
Seems to be a reasonable product.