OWC 4GB PC8500 DDR3 1066MHz SO-DIMM Memory Compatible with Early 2009, Early 2010 MacBook, MacBook Pro Unibody Models, 2009/2010 Mac Mini, and 2009 iMac Models
Corsair CMSA4GX3M1A1066C7 Apple Certified 4GB (1x4GB) DDR3 1066 MHz (PC3 8500) Laptop Memory 1.5V at Amazon.com