Aliexpress
Click here… to search for Surpass Hobby ROCKET 540 V4S Modified Sensored RC Motor on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Coupon (146.99 USD): BGcce354
(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): BG531479, BgGoodie9, TTBLACK5
(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 Surpass Hobby ROCKET 540 V4S Modified Sensored RC Motor is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).