Where to buy a GOOD Memory Card for 2019 iMac

I have an iMac (Retina 5K, 27-inch, 2019) computer currently running with 32 GB memory, and able to go up to 64. I would really like to up the memory to 64 GB due to a few programs I am starting to get into using that are straining the 32 GB, but I get very lost with all of the millions of options for the cards to buy, and I don't want to risk hurting my computer by misunderstanding what I'm installing.

Is there a recommended brand or product to buy so I know I'm not getting something spammy/low quality?