A-Tech for Apple 6GB Kit (1x2GB + 1x4GB) DDR2 667MHz PC2-5300 200-pin SODIMM for MacBook (Late 2007, Early 2008, Early 2009), MacBook Pro (Mid 2007, Early 2008), iMac (Mid 2007) - Memory RAM Upgrade at Amazon.com
Crucial 4 GB 1X4 GB PC2-6400 DDR2-800 MHz 200 pin RAM non ECC SO-DIMM non registrata | eBay