Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. One coupon is available. Cool!
Link: Banggood product page
Coupon (59.49 USD): BGherra
(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): 05MYSUP, TA12, TTxBG10, BG4650, TS15prime, BGAT18, bGhOnEy10, BgcLuBofErtA10
(probably won’t work, but you can try them out)
Price history and price alert
Do you need price history chart (for all/most countries) for AC110V/AC220V To DC 48V 20A 1000W Power Supply? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).