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
KTH-XW667/2G Kingston 2GB Kit (2 X 1GB) PC2-5300 DDR2-667MHz CL5 DIMM DR Memory | eBay
2GB 2 X 1GB PC3200 400MHz 184 pin DDR SDRAM Non-ECC DIMM Desktop Memory for Dell Dimension 3000 (PARTS-QUICK Brand) at Amazon.com