Aliexpress
Click here… to search for Outdoor Knife Sharpener on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Coupon (8.82 USD): BGherra
(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): bgsport, TTxBG10, TOOLS15, 502C6B, BG2020NS, BGMPB2020, BGAFF10OFF, bGhOnEy10, BgcLuBofErtA10, BG592dca
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Price history (for all/most countries) for Outdoor Knife Sharpener is here.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).