When trying to describe someone who looks very similar to another person, you might use the phrase "be a dead-ringer for," but there are many other phrases out there that can convey the same meaning. For example, you might say that someone is a spitting image of another person, or that they are a perfect match in terms of appearance. Other options might include describing someone as being a doppelganger or lookalike, or simply saying that they bear a striking resemblance to another person. Ultimately, the best way to convey this meaning will depend on the context in which it is being used and the specific nuances you want to convey.