Basically copy coupon, view price history or create e-mail price alert. Best price?
1x Allen Key (For replace the tips and heating element), 1x TS-I Solder Tip (Find more types in SKU253283), 1x Bracket, 1x Earth Clamp, 1x TS100 UpGrade Digital LCD Soldering Iron (Classic Model in SKU252598)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($51.83): BGherra
2. ($51.83): BGTool15
3. ($54.88): BGAFF10OFF
4. ($54.88): bGhOnEy10
coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): randyTS100, chollodrones05, aff7off, 502C6B, AFfbG10, BG23SW, BGTS100UP, BG15sh, BGVDay10%off, BGMPB2020, BGdragonBoat, BGSS10%SW
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – MINI Upgrade Brown TS100 OLED Soldering Iron [EU/CZ] ($-3)
Price history and price alert
Price history (for all/most countries) for MINI Upgrade Brown TS100 OLED Soldering Iron is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).