Aliexpress
Click here… to search for T-Motor TM-2419 HD Drone PNP on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (235.58 USD): Drones6
(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): BGTHD, TTxBG10, BG2419, 2019SPEDM, bgssaff9, AFfbG10, BGWK2419, BG2419HD, 502C6B, BGBFCR25, BGCITYADS2019, BGVDay10%off, BGAFF7OFF, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BG10RACING, BGMATT7, BGDAVIS
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for T-Motor TM-2419 HD Drone PNP.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).