Crucial 32GB Kit (2 x 16GB) DDR4-2666 SODIMM Memory for Mac | CT2K16G4S266M | Crucial.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
Amazon.com: OWC 2GB (2 x 1GB) PC5300 DDR2 667MHz SO-DIMMs Memory Compatible with MacBook/MacBook Pro, iMac, and Mac Mini Models (OWC5300DDR2S2GP) : Everything Else