Amazon has "The Darkest Hour" for sale for $10 in 4K Ultra HD + Blu-ray + Digital formats. The digital code is Movies Anywhere (MA) eligible. Shipping is free with Prime.
https://www.amazon.com/Darkest-Ho…07BZC8BB3/
Update:
Also available at Walmart:
https://www.walmart.com/ip/Darkes…465517