"OXO Good Grips 5-Pound Food Scale with Pull-Out Display, Black"
which is $25 on Amazon. It measures to 1 gram or 1/8 ounce. It claims that my cue is 521 grams or 18 3/8 ounces. Those two numbers match with a gram. A gram is about a thirtieth of an ounce.
Get a good food scale or postage scale. but any electronic scale up to 2 lbs measurement.
Weight should be expressed in both grams & ozs but grams is a more accurate measurement.
Just do a search on ebay and you find plenty to choose from.......think about gettng a calipers too.