Get a decent[1] external SAS adaptor, a SAS cable, and a second hand enclosure and bob's your noisy uncle!
something like this: https://www.bargainhardware.co.uk/dell-powervault-md1220-sto...
https://www.bargainhardware.co.uk/hp-z800-z820-external-mini...
Your workstation might even have a sas controller on it already.
This might be overkill, but even with spinny disks you'll be able to get fast random io[2]
[1] subjective. If yours is an enterprise workstation you'll most likley be able to get an official SAS controller for it.
[2] well about 10 iops per drive.