I did a brief search and found this string. There are several other references in the data base that may be helpful if this one does not give you what you need.
Paul
http://us.lexusownersclub.com/forums/index.php?showtopic=9147&st=0&p=396032&hl=+es300%20+tail%20+light%20+bulb&fromsearch=1entry396032