B&H Photo Video has the 16TB Expansion Desktop drive on sale for $308.99, shipping is free. It's currently on backorder; my last drive which was on backorder (same SKU) shipped out within a week after placing the order.
If you're interested in shucking the drive, you will find a Exos X16 Enterprise drive inside.
No doubt, there will be some Seagate detractors out there, but I haven't experienced any drive failures with any of my recent Seagate Ironwolf drives. Same can't be said for the HGST (now WD) 10TB Nas drives I purchased over the last 4 years. YMMV
Also available on Amazon for the same price, in stock and ready to ship. QA Update: Temp OOS but orderable