@zapcost Its 500$ here: https://www.amazon.com/dp/B01B6BN1CU/
Update: the one you mention is myCLOUD series, more expensive as its Network Drive (slower for Burst and better for file sharing). The one I mentioned is myBOOK series.
@pr0cesor I compared the single mybook (white WD) and the mybook Duo (RED WD) with prices of 418$ (single) vs. 499$ (Duo). Check 4th post up.