OWC 32GB PC21300 DDR4 2666MHz SO-DIMM Memory Compatible with Mac Mini 2018, iMac 2019 and up, Dell, HP, Lenovo, ASUS and Compatible PCs (OWC2666DDR4S32G) at Amazon.com
CORSAIR VENGEANCE LPX 32GB (2PK x 16GB) 3600MHz DDR4 C18 DIMM Desktop Memory Black CMK32GX4M2D3600C18 - Best Buy
Amazon.com: OWC 32GB (2 x 16GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S32P) : Everything Else