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 (23.37 USD): BGGAL8
Coupon (23.37 USD): BGRCParts8
(CouponsFromChina.com tip: put item in your cart and apply coupon code there 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): BGV21506, AFfbG10, BG12MRP, BGVDay10%off, BGMPB2020, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGDAVIS, BGHONEY2110, Parts8
(there’s a little possibility that old coupon will work)
Price history and price alert
Check out price history chart (for all/most countries) for RCINPower GTS-V2 1506 4-6S RC Motor.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).