Successful patch on iMac 12,1 (Mid-2011) : r/MontereyPatcher
Best Buy: Apple® 21.5" iMac® 4GB Memory 500GB Hard Drive MC309LL/A
Apple iMac A1311 21.5" AiO Computer i5-2400S (Mid-2011) -
Apple iMac 2.7Ghz i5-2500S 27-Inch (Mid-2011) *NO HDD/RAM* – MSU Surplus Store
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
Apple iMac 2011 (Mid) 27-inch 2K (iMac 12,2) SSD ,Ram & OSX Upgrades - ZD Laptop Service Centre
Apple iMac 12,1 A1311 - i5 - 4GB RAM - 500GB HDD - Zer shop
Apple iMac 12,1 A1311 - i5 - 4GB RAM - 750GB HDD - Zer shop