I am monitoring price for For Sidewinder X1 and it is for 39.99 USD now (in Banggood). You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
Latest coupon and price update (UTC):
Banggood (39.99 USD)
Banggood warehouse is located in China. I’m afraid that there’s no working coupon in Banggood. I think you want to know if the price is good. Well, this price is higher than average price (37.26 USD)
Link: Banggood product page
Price: 39.99 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BG8FORMULAMX
(these coupons are old, so probably won’t work)
Aliexpress
Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for Artillery All-in-one Single Extruder Kit for Sidewinder X1 3D Printer.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).