Can't help in regards to using Amazon, but some of the Lenovo Minis have an m.2 slot on the underside, as well as the 2.5 drive in the top. I think the M920q and some others have two m.2 slots.
If you want maximum jank, you can split the m.2 into 5 SATA ports, then leave the bottom panel off and to connect to drives in your drive bay. That's what I've done. You'll need a separate power supply for the drives, though.