That's the type of scale I have; it's digital and cost about $30. I take it with me every time I visit REI, much to the horror of the clerks. With a gram function, it can be used for cooking with European recipes, too. It will even weigh your mail! I tested its accuracy at tax time (weighed the return at home and had it weighed again at the Post Office).

My bathroom scales weigh to 0.1 lb., so I can use them for stuff weighing more than 5 lbs., such as my loaded pack.