LoREX is an acronym for "low release and exposure". The term appears in appears in documents released by the U.S. Environmental Protection agency in conjunction with chemical manufacture. Low release refers to something that happens slowly over a long period of time.
Lurex was a trademarked brand of socks made in the late '60s and early '70s. They had shiny metal threads woven through them. A commenter on AC/DC FAQ suggests that the metal threads refers to heavy metal rock. Another possibility is that Lurex was worn by glitter rock performers as part of their costumes.
Let's carry this investigation a little further. LoREX has several applications in the manufacture of paper and cloth. The term appears in documents governing chemical manufacture, especially polymers. Polymers are used to coat some types of paper and polyester fibers. Polyester fibers are often used to make yarn, and would probably be a part of the manufacture of the metallic threads in Lurex.
Polyester fibers are often used in the manufacture of modern socks. They are added to cotton yarns, which are knitted into socks, making them stretchy and more comfortable. Incorporating glitzy threads into the knit would make them sparkly, but would also add some chemical processing to the yarn, which would bring them under the scrutiny of the EPA. LoREX socks would be in keeping with the insouciant attitude AC/DC sometimes portrays, as in "Dirty Deeds Done Dirt Cheap" and also an environmental statement.
Lorex Technology manufactures electronic security systems. This may be reaching, but the thought of having socks that were wired for security seems just quirky enough for AC/DC lyrics.
Whether we are talking about socks with a lot of bling in the form of metallic threads or socks that are slowly releasing chemical compounds thanks to being made from outgassing polymer fibers, or even socks wired for security, the lyric is saying, "Hey look! I've got cool socks, I've got cool shoes, I've got all the stuff that goes with being a famous rock star."