OWC 8GB (2 x 4GB) PC12800 DDR3L 1600MHz SO-DIMMs Memory Compatible with 2011-2015 iMac, 2011-12 Mac Mini, and 2011-2012 MacBook Pro (Non-Retina Display) Models (OWC1600DDR3S08S) at Amazon.com
A-Tech 4GB RAM Replacement for Crucial CT2KIT51264BF160B | DDR3/DDR3L 1600MHz PC3L-12800 2Rx8 1.35V SODIMM 204-Pin Memory Module at Amazon.com
Synology RAM DDR3L-1866 SO-DIMM 4GB (D3NS1866L-4G) at Amazon.com