A-Tech 16GB (4x4GB) RAM for Apple iMac (Mid 2010, Mid 2011, Late 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
Timetec 32GB KIT(4x8GB) Compatible for Apple DDR3L 1600MHz PC3L-12800 CL11 for iMac (Mid 2011, Late 2012, Late 2013, Late 2014 Retina 5K, Mid 2015 Retina 5K) SODIMM Memory Module MAC RAM Upgrade at Amazon.com
32.0GB OWC Memory Upgrade Kit For 2010-2011 Apple iMac
Apple Launching Pilot Program Allowing Repairs of Soon-to-Be Vintage Mid 2011 iMac in United States - MacRumors
Apple iMac Mid 2011 Price in Pakistan – Used All-in-One Core i5 8 GB RAM 500 GB HDD 1 GB Graphic Card 27″ and 15 Days Warranty - IT International
Install memory in an iMac - Apple Support (IN)
Apple iMac 2.5Ghz i5-2400S (Mid-2011) *No HDD/RAM* – MSU Surplus Store