Basically copy coupon, view price history or create e-mail price alert. Best price?
Material Stainless Steel, Color Black + Silver, Size 3.8x 8.5x 20cm, Weight 250g, Model ML-KS2
Aliexpress
I could not find it 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. ($11.47): BG3Q5
2. ($12.15): bGhOnEy10
apply it in your 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): BGMLKS2, TTxBG10, bgssaff9, AFfbG10, BGBFAFF2019, BGCITYADS2019, BGminleaf, BG322e14
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Here is price history (for all/most countries) for Minleaf ML-KS2 4 In 1 Sharpener.
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)).