Amazon.com: OWC 8GB (2 x 4GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S08P) : Everything Else
8GB (2 X 4GB) DDR3 1600MHz PC3-12800 240-pin Memory RAM DIMM Kit for Desktop PC by NEMIX RAM at Amazon.com
v-Color 64GB (2 x 32GB) ECC SO-DIMM DDR4 2666MHz (PC4-21300) for microservers, workstations, Networking Platforms and Embedded Systems 2Rx8 CL19 1.2V (TES432G26D819K-VC) at Amazon.com
Crucial 16GB 2 x 8GB DDR4-2400 PC4-19200 CL17 SO-DIMM Memory Kit - 2K8G4SFS824 - Micro Center
OWC 96GB (2 x 16GB + 2 x 32GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Compatible with 27" iMac w/Retina 5K (Early 2019 and up) and Compatible PCs (OWC2666DDR4S96S) at Amazon.com
2GB Kit (2 x 1GB) DDR PC2700 Unbuffered Non-ECC 184-PIN DIMM - CT2KIT12864Z335 at Amazon.com
Crucial 32GB (2 x 16GB) 262-Pin DDR5 SO-DIMM DDR5 4800 (PC4 38400) Laptop Memory Model CT2K16G48C40S5 - Newegg.com