Hasbro released a 3.75" version in 2006 but there is going to be a bigger one. Hasbro announced that there will be a six inch version next year.
https://www.hollywoodreporter.com/movies/movie-news/star-wars-george-lucas-stormtrooper-1235021938/
https://www.hollywoodreporter.com/movies/movie-news/star-wars-george-lucas-stormtrooper-1235021938/