Apple iMac 21.5-Inch (Late 2013) "Core i5" 8GB RAM 1TB HDD Intel Iris Pro | eBay
Apple iMac 21.5″ 2013 – i5 – 2.70 GHz (i5-4570R) Processor, 8GB RAM, 1TB HDD, Catalina, Grade B | Green Dragon Technology
I got a FREE 2013 iMac 21.5 with internal upgrades including Samsung evo ssd and 16gigs of ram. Then used open legacy patcher to install Mac OS Venture 13.5 beta. : r/osx
Memory Upgrades for iMac 21.5-Inch 2012 - Late 2013