8GB (1x8GB) DDR3-1600MHz PC3-12800 2Rx8 SODIMM Laptop Memory by NEMIX RAM at Amazon.com
TEAMGROUP Elite DDR3 8GB Single 1600MHz (PC3-12800) CL11 Unbuffered Non-ECC 1.5V UDIMM 240 Pin PC Computer Desktop Memory Module Ram Upgrade - TED38G1600C11-S01 - (1x8GB) Single at Amazon.com
Crucial 8GB DDR3 1600MHz PC3-12800 Registered DIMM Server Memory CT102472BB160B at Amazon.com
OWC 8 GB (2 X 4GB) ram PC8500 DDR3 1066MHz sodimm 204-pin Memory Upgrade Kit, (OWC8566DDR3S8GP), Compatible with MacBook Pro, MacBook, Mac Mini and iMac at Amazon.com