Hello I am a solicitor with over 15 years experience I will try to help you with this.
I assume this was a private sale and that the person you brought from was not selling in the course of business.
yes that's correct
If you have bought something based on a description that turns out to be a misrepresentation. You relied on that representation as being true and the nature of that representation (ie that they were original Range Rover wheels) was central to you entering the contract then yes you have been the victim of a misrepresentation and are entitled to treat the contract as null and void, if you are unable to agree a lesser price. His lack of knowledge is irrelevant.