Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Coupon (328.99 USD): 13f142
(CouponsFromChina.com tip: this code has to be applied in your 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): Wholesale20, BGBFCR28, BGCITYADS2019, Email5, BGMPB2020, bGhOnEy10, BGAFF7OFF, BGYEPA6, BGYEPA6S, BGYEESA7, BGYEESA9, BGYEESA8, 7d18f7
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Price history (for all/most countries) for YEPO 737A6 8/128GB Laptop is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).