Sound the alarm! The arbiter of chic, modest style , Her Royal Highness Princess William, Duchess of Cambridge, Countess of Strathearn, Baroness Carrickfergus — or Kate Middleton, for short — is back with yet another reason for us to sing her stylistic praises. On Thursday evening, the monarch stepped out in a bargain-priced Self-Portrait dress at the premiere of A Street Cat Named Bob, and guess what? You can actually buy it.The dress, previously worn by OG party girl Paris Hilton, rings in at approximately $400 , meaning if you basically eat air (or excavate the crannies of your quarter-filled couch) for the next, say, month, you, too, can dress like a princess. Not for nothing, the dress is really chic, and sort of reminds us of Middleton's famous wedding dress designed by Sarah Burton, the current lead at Alexander McQueen. The caveat? The dress is currently available only for pre-order and won't be shipped until January of next year, so yeah.This floor-length lace look is the first time Middleton has worn Self-Portrait. That means not only is this another do-good look for the books for the Duchess of Cambridge, but it's brilliant exposure for the indie brand. Back in September, the label gave us some fresh takes on the off-the-shoulder trend, and we've been keeping up with it ever since. As for Middleton's latest red carpet choices that include Erdem and Kate Spade, we're keeping our fingers crossed for a Céline Dion-esque Vetements moment in the future. A kid can dream, right?