Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (394.68 USD): BGMatt2022
(CouponsFromChina.com tip: paste coupon code in your cart and click Apply 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): Cuponation9, BgGoodie9, BGApex10
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Here is price history (for all/most countries) for Emax Hawk Apex 162mm 3.5inch 4S Drone BNF ELRS.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).