Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (130.19 USD): BGMATT7
Coupon (130.99 USD): 7bcdf9
Coupon (130.99 USD): BGAFF10OFF
Coupon (130.99 USD): BG10RACING
Coupon (130.99 USD): BGCuponation10
(CouponsFromChina.com tip: apply it 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): affbg10, BGT339, AFfbG10, BG339Pro, BGDroneRc108, BGRGTB339, BG15G339, BGCITYADS2019, BG339P, BGDB339, BGBINKUPON11, BGSFD3, BGVDay10%off, BGW339, bGhOnEy10, BGGTB339PI, BGdragonBoat, BGSS10%SW, BGB339, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for Diatone GTB339 Cube 3S PNP Drone? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).