OWC 4GB PC5300 DDR2 667MHz SO-DIMM Memory RAM Upgrade Compatible with MacBook (Late 2007/Early 2008), MacBook Pro (Mid/Late 2007, Early 2008), & iMac (Late 2007) with Core 2 Duo CPU (OWC5300DDR2S4GB) at Amazon.com
RMN1150EG38D6F 512MB 1Rx8 DDR2 SO-DIMM PC2-5300 667MHz 200-Pin Non-ECC CL5 1.8V Laptop Memory Module RMN1150EG38D6F-667 Compatible Replacement Spare Part for Ramaxel Compatible and Other Systems at Amazon.com
414046-001 1Gb Ddr2 667Mhz Pc2-5300 200-Pin Cl5 Non-Ecc Unbuffered So at Amazon.com