Aliexpress
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Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (57.91 USD): BGherra
Coupon (57.91 USD): BGWELDTOOL
(CouponsFromChina.com tip: put item in your cart and apply coupon code there 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): bGpAnDacHeCk, AFfbG10, BGVDay10%off, BGAFF10OFF, bGhOnEy10, BGRUS15, BG8a7644
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Here is price history (for all/most countries) for STM32 V2.1S T12 OLED Soldering Station.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).