we know that the physical size of NAS or mini-ITX case are almost the same in the market. sometime we might see it wrongly. Somehow, the question posted about CFI-A7879, this is mini-ITX case only, not NAS. we only called it NAS if come with complete feature(both software/hardware) then ready to serve file storage purpose in OOBE. Yes, you can buy this casing and DIY then called it NAS once complete, it's design for NAS. below are the spec of CFI-A7879:

Model Name: CFI A7879 Mini ITX Server Chassis
Chassis Cooling: 12cm Low Noise Case Fan
Drive Bay (s): 4 x 3.5" Hot Swappable HDD Trays
Expansion Slot (s): 1 x Expansion Slot
Front Panel: 2 x USB 2.0 Ports (2.54mm pitch) /  Power On/Off Button and LED indicator / Storage Activity LED
Power Supply: 200W FlexATX Power Supply w/PFC
Dimensions: 7.88"(W) x 9.85"(H) x 11.82"(D)

back of CFI-A7879:


@bad melatonin, the chassis brand is Chyang Fun Industry; hardly see here but you can try contact rockrock, since he sell CFI chassis before but not sure he can help you source this model A7879 or not.