As part of their daily DealZone (today only), B&H Photo is offering a discount on the SanDisk 256GB Extreme PRO CFexpress Type B memory card. See all available SanDisk CFexpress memory cards here.
Here is an updated list of CFExpress companies:
In the US, CFexpress cards are sold at Adorama, B&H, and Amazon.
In Europe, CFexpress cards can be found at Amazon UK, Amazon France, Amazon Italy, and Amazon Spain.