"Not quite, but I applaud you for not assuming everything you hear is correct." It was rare to actually see people of the magical world not assume something they heard to be true. It was just a giant rumor mill that grounded out falsities like candy. Professor Slughorn was usually one who did, wanting to be with the in crowd. To know that he occasionally has sparks of critical thinking was nice.  "Depending on how the harvesting goes, you might see Basilisk components on the market soon." It was a slight lie. There were many other aspects that Harry and Sirius had to deal with before they could be on the open market. 