I just use a Frankfort Arsenal scale that I use for reloading. Should be about 24 bucks at brownells or any place that sells reloading supplies.
For the money OMA scales are hard to beat , I have two and they have lasted and worked for a long time without any hiccups. Once they are calibrated and set...takes a couple minutes, very easy to do...after that all you have to do is turn them on.