I've been to some random LFS that aren't exactly knowledgeable when it comes to CA/SA cichlids and have found some surprises mixed in their tanks. I can't say that I have ever found anything "rare" but I have found a few fish that are uncommon to most stores in this area. This happens a lot with juvenile fish. Unless a person knows what they are looking for, many juvenile cichlids can look the same. I have spotted several mislabeled fish this way. That's the great thing about reading and learning more and more about cichlids. You'll have the eye to spot the gems hidden in assorted cichlid tanks.