NEMIX RAM 32GB (4x8GB Upgrade) DDR3-1333 PC3-10600 204-Pin SODIMM Memory for Apple MacBook Pro Early/Late 2011, iMac Mid 2010 27 inch 4-Core, iMac Mid 2011 21.5/27” , Mac Mini Mid 2011 at Amazon.com
Install memory in an iMac - Apple Support
Apple Launching Pilot Program Allowing Repairs of Soon-to-Be Vintage Mid 2011 iMac in United States - MacRumors
Apple iMac 27" All-In-One Computer, Intel Core i5, 4GB RAM, 1TB HD, DVD Writer, Mac OS X 10.7 Lion, MC813LL/A - Walmart.com