I would take it to a Lexus shop. These type of cars if you are unfamiliar with their systems may end up costing your more than the repair itself. I am all for doing it yourself but, especially Japanese vehicles and even more so a Lexus require the "special" parts and knowledge to repair something of this type and if your asking on this site for a fairly technical repair job, I would recommend taking it to a reputable repair shop that guarantees their work, Get a few prices and you will get the idea!
