Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (125.99 USD): bGhOnEy10
Coupon (125.99 USD): bgshOOp10
Coupon (125.99 USD): BgcLuBofErtA10
(CouponsFromChina.com tip: apply code in your basket (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): BGGTB329P, BGdragonBoat, BGSS10%SW, BGRC902, BgoFErTaSchInA10
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for Diatone GTB 329 Pro Cube AIO Drone is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).