Apple iMac 21.5" All-in-One Desktop Computer Core i5-4570R 2.7GHz 8GB RAM 250GB HDD Mac OS Mojave Late-2013 w/ Keyboard & Mouse
Memory upgrade: Apple iMac 2012/2013/2014 (Howto)
Memory Upgrades for iMac 21.5-Inch 2012 - Late 2013
Best Buy: Pre-Owned Apple iMac 21.5-inch Desktop "Core i5" 2.9 (Late 2013) 8GB Memory 1TB HDD ME087LL/A
Amazon.com: Apple iMac 21.5in 2.7GHz Core i5 (ME086LL/A) All In One Desktop, 8GB Memory, 256GB Solid State Drive, MacOS 10.12 Sierra (Renewed) : Electronics