Item Xiaomi FREETIE Insoles, Sports Shoes, Material TPU, EVA, 43-44, Upper material 100% Polyester, 41-42, Size 39-40, Csual Shoes, Suitable For Leather Shoes.
Basically copy coupon, view price history or create e-mail price alert. Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There is one great coupon!
Link: Banggood product page
1. ($15.19): BG00c906
apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): e2bcea, 600fa9, TTxBG10, BGSMB5, AFfbG10, bGhOnEy10, BGCS5227, BGRSHOES, BGXIAOMI10TH, BGwhielabel, BG10OFFAFF1, BG4d9120, BG1074d6, 00c906, ADMITAD2212, 2022ACTIESNL, Terence, Tabby20, 2203ActiesNL, BG1efeb0, MVC8SPRING, 8BGwbg2204, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BGeb5395
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi FREETIE EVA Shock Absorption Insole. The lowest price was: $5.89.
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)).