DIY data backup suggestions

I have an old OWC Mercury Elite-AL Pro Qx2 4 Bay Hard drive RAID Enclosure (1st generation) but I can't get it to be recognized by a computer. Mostly trying with linux over usb.

I've been thinking about maybe removing the electronics in it and just using it as an enclosure. It holds 4 drives nicely with a fan. Any thoughts about what I could use, I'm fine with just a USB interface. I don't need fast data access.

EDIT: other hardware I already have that could be useful:

• 1 - Intel NUC NUC5i7RYH
• 1 - Intel NUC NUC6CAY
• 2 - PINE A64+ 1GB