NEMIX RAM 16GB Kit (2x8GB Upgrade) DDR3-1600 SODIMM PC3-12800 for Apple MacBook Pro Mid 2012 / iMac Late 2012 / iMac 2013, Late 2014, Mid 2015, Mac Mini Late 2012 at Amazon.com
A-Tech 16GB Kit (2x8GB) RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz PC3-12800 SODIMM 204-Pin Memory Upgrade at Amazon.com
CMS 16GB (2X8GB) DDR3 12800 1600MHz Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® MacBook Pro Core I5 2.5 13" Mid-2012 - A7 at Amazon.com
MacBook Pro (13-inch, Mid 2012) Hard Drive (and possibly RAM) replacement : r/mac
Memory RAM Upgrades for MacBook Pro (2012 - Late 2016)
MacBook Pro: How to remove or install memory - Apple Support
Apple MacBook Pro 13.3" MD102LL/A Mid 2012 - 8GB RAM - 750GB HDD - 2.9GHz Intel Core i7-3520M (Scratch and Dent) - Walmart.com
16GB 2X8GB RAM Memory for Apple MacBook Pro 2.9GHz Intel Core i7 (13-inch DDR3) Mid-2012 Black Diamond Memory Module DDR3 SO-DIMM 204pin PC3-12800 1600MHz Upgrade - Walmart.com