Materials: Plastic.
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
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.
Link: Banggood product page
1. ($8.31): BGTOYSALES
2. ($8.49): BG8RCToy
3. ($8.68): BG00c906
just apply this code in your 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): AFfbG10, BGVDay10%off, BGAFF10OFF, BGTT10, bGhOnEy10, BGdragonBoat, BGSS10%SW, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BGHONEY2110, BANGGOODSD, BGc7b765, 00c906, ADMITAD2212, 2022ACTIESNL, Terence, Tabby20, 2203ActiesNL, BG1efeb0, MVC8SPRING
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for Plastic Rainbow Magic Spring? There we go. The lowest price was: $0.86.
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)).