YMMV (low stock) Crucial M4 512GB 7mm SSD $407.99 with Transfer Kit CT512M4SSD1CCA at buy.com
has the 7mm drive
Crucial M4 512GB 2.5" SATA III Solid State Drive (SSD) with Data Transfer Kit for $407.99
5% Cashback through Shopdiscover.
7mm drives typically have not been hitting such low prices or are sold out.