3.5 enclosure with fan

Hello, I’m looking to buy 2 enclosures for 2 WD Blues (8TB). Any good recommendations for some enclosures? Must have built in fan. What enclosures do you use? Also, would 2 be necessary? If not are there any precautions to take while storing the extra HDD without an enclosure? I was thinking it’s probably best to keep them both in separate enclosures instead of buying one and using it for both when needed, this is for long term storage and will mostly be stored away.