Aliexpress
Click here… to search for OUKITEL WP19 21000mAh G95 8/256GB on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong. You can get coupon down below.
Link: Banggood product page
Coupon (469.19 USD): BG8ReviTrage
(CouponsFromChina.com tip: coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGHU2240, BGJUNEGSG9, BgGoodie9
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for OUKITEL WP19 21000mAh G95 8/256GB is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).