Aliexpress
Click here… to search for UMIDIGI BISON X10 Waterproof NFC 6150mAh 6.53 inch 4/64GB P60 on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong. Hmmm… There is no active coupon in Banggood at this moment.
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Old coupons (from the oldest to the newest): BG1c4d70, 2022ACTIESNL, Terence
(there’s a little possibility that old coupon will work)
Price history and price alert
Here is price history (for all/most countries) for UMIDIGI BISON X10 Waterproof NFC 6150mAh 6.53 inch 4/64GB P60.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).