Apple Macbook Pro 13 inch Early 2011 2.3 GHz Intel Core i5 16GB RAM 500GB SSD | eBay
A-Tech 16GB (2x8GB) RAM for Apple MacBook Pro (Early/Late 2011), iMac (Mid 2010 27 inch 4-Core, Mid 2011 21.5/27 inch), Mac Mini (Mid 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
OWC 16GB (2x8GB) ram Upgrade PC3-12800 DDR3L 1600MHz sodimm 204 Pin CL11 Memory Upgrade Kit Compatible with Late iMac, Mac Mini, and MacBook Pro Computer at Amazon.com
Rasalas 8GB Kit (2X 4GB) PC3-10600 DDR3 1333 MHz SODIMM RAM Upgrade for AMD Intel Laptop, MacBook Pro 13/15/17 inch Early/Late 2011,iMac 21.5-inch Mid/Late 2011,27-inch Mid 2011,Mac Mini 5,1 & 5,2 Mid
MacBook Pro 13" Unibody Early 2011 Logic Board Replacement - iFixit Repair Guide
Apple MacBook Pro (13-inch, Early 2011) 2.3GHz Intel Core i5, 6GB RAM, 128GB SSD | eBay
MacBook Pro: How to remove or install memory - Apple Support
Amazon.com: Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3L 1600MHz for Mac Book Pro(Early/Late 2011,Mid 2012), iMac(Mid 2011,Late 2012,Early/Late 2013,Late 2014,Mid 2015), Mac Mini(Mid 2011,Late 2012) MAC RAM : Electronics
Amazon.com: Apple MacBook Pro 13 inches MC700LL/A (4GB RAM, 320GB HD, macOS 10.13) - 1 Pack (Renewed) : Electronics