Amazon.com: Apple iMac 21.5 inches Retina 4K i5-8500 8 256GB SSD Radeon Pro 560X Silver MHK33LL (Renewed) : Electronics
A-Tech 8GB RAM for Apple MacBook Pro (Early/Late 2011), iMac (Mid 2010 27 inch 4-Core, Mid 2011 21.5/27 inch), Mac Mini (Mid 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Module at Amazon.com
CMS 16GB (4X4GB) DDR3 10600 1333MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core I3 3.06 21.5-Inch (Mid-2010) - A28 at Amazon.com
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
Amazon.com: Original Graphics Video Card Replacement for Apple iMac Core i3 3.2 Mid-2010 21.5 Inch Desktop Computer A1311 MC509LL/A MC509, AMD ATI Radeon HD 5670 GDDR3 512MB, GPU Board Repair Parts : Electronics
Amazon.com: ShineBear Power Supply 205W for iMac 21.5" A1311 Late 2009 Mid 2010 Mid/Late 2011 614-0444 OT8043 - (Cable Length: 0.2m) : Electronics
Amazon.com: OWC 2.0TB HDD Upgrade Kit Compatible With 2009-2010 iMacs, Includes: Thermal Sensor, Tools, 2.0TB Hard Drive : Electronics
Amazon.com: Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3 1333MHz PC3-10600 CL9 for Mac Book Pro (Early/Late 2011 13/15/17 inch), iMac(Mid 2010, Mid/Late 2011 21.5/27 inch), Mac Mini(Mid 2011) MAC RAM Upgrade :
Amazon.com: Lecho Front Glass Bezel Replacement for iMac 21.5 Inch A1311 Year 2009 2010 2011 : Electronics
OWC 2.0GB PC10600 DDR3 1333MHz SO-DIMM Compatible with 2011 MacBook Pro, Mid 2010/2011 21.5" & 27" iMac Models, 2011 Mac Mini (OWC1333DDR3S2GB) at Amazon .com