If you just have the "bare" HD, don't buy an enclosure at all.
Instead, buy a USB3/SATA docking station. To see what's available, go to amazon, and enter "usb3 sata dock" in the search box, and you'll get many hits.
The advantage of having a dock is that you can use the drive you have..... or another drive.... or another drive..... -- you don't have to be fooling with enclosures.
The drive will behave "as if" it were an "enclosed" drive. You can boot from it, etc.
The only disadvantage is that it doesn't look quite as "clean" as would a drive enclosure. But the benefits of "swap-ability" outweight that (at least for me).
I've had good experiences with docks from plugable.com (no financial interest other than being a paying customer).