You would just want to buy an eSata enclosure or dock like these ones below, and then put the HDD of your choosing in it. eSata enclosures aren't that common these days, but there are usually a few to be found.

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https://www.amazon.com/Vantec-NexStar-Gen1x1-Enclosure-NST-358SU3-BK/dp/B0BDKG16XT/

https://www.amazon.com/StarTech-com-eSATA-Enclosure-Trayless-S351BMU33ET/dp/B076M3ZLKF/

https://www.amazon.com/StarTech-com-eSATA-Drive-Docking-Station/dp/B00KILQOG0/