I currently have the Asus PCE-AC68 Dual Band Wireless PCI Express Network Interface Card
I am happy with it, good reception, good speed. No issue really, other than the fact that it’s a Broadcom chipset and can break with a Kernel update 
Is there a product equivalent I could purchase that would be 100% Linux friendly?
For Wi-Fi 5 (802.11ac) capability, choose a card with the Intel 9260 chipset. (The newer Intel AX200 or AX210 chipsets provide Wi-Fi 6 connectivity if that is desired, but obviously only relevant if you have a Wi-Fi router providing such capability as well.)