Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I can’t find any active coupons for this product in Banggood.
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BG1081b2, BG00c906, ADMITAD2212, BG1d402f, BGMUSIC10, BG1b22ab, BG824f04, BG6d78ac, BG589b2e
(there’s a little possibility that old coupon will work)
Price history and price alert
Here is price history (for all/most countries) for DIY Hand-Cranked Music Box 15 Tone.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).