Apple iMac All-in-One Desktop 27-inch (5K) 3.6GHZ 8-Core i9 (2020) 10TB HD & 512GB Flash & 64GB RAM-Mac OS/Win 10 Pro (Used) - Walmart.com
OWC 64GB (2 x 32GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs (OWC2666DDR4S64P) at Amazon.com
Apple iMac All-in-One Desktop 27-inch (5K) 3.6GHZ 8-Core i9 (2019) 2TB HD & 64GB RAM-Mac OS/Win 10 Pro (Used) - Walmart.com
64GB (4x16GB) DDR4-2666MHz PC4-21300 SO-DIMM Memory for Apple 27" iMac with Retina 5K Display Mid 2020 (iMac 20,1 iMac 20,2) by NEMIX RAM - Newegg.com
OWC Confirms New Low-End 27-inch iMac Can Be Fitted With 64GB RAM - MacRumors