Aliexpress
Click here… to search for iFlight SucceX-E F4 Flight Controller OSD 45A 2-6S ESC on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (88.31 USD): BGRCParts8
(CouponsFromChina.com tip: you should apply the coupon 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): BGCITYADS2019, BGGEPPart, AFfbG10, BGVDay10%off, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSXEF4, bgshOOp10, BGRC902, BgoFErTaSchInA10, BGSUXF4, BgcLuBofErtA10, BGXESTK, BGCuponation10, BGDAVIS, BGHONEY2110, Bgdronepro2, Parts8, Tabby20
(probably won’t work, but you can try them out)
Price history and price alert
Check out price history chart (for all/most countries) for iFlight SucceX-E F4 Flight Controller OSD 45A 2-6S ESC.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).