Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (52.35 USD): BGPROBuscape
Coupon (55.43 USD): BGAProjector
(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): TECH8%, PICODICOM, aff7off, BG3CSUM, bgssaff9, BGaDmITAd, bgchinafest, BGBFAFF2019, BGCITYADS2019, bGpAnDacHeCk, FBCOUPON1, bGhOnEy10, BGdragonBoat, BGAFF7OFF, bgshOOp10, BgoFErTaSchInA10, BGAFF10OFF, 7d18f7, 13f142, BGProjectors
(probably won’t work, but you can try them out)
Price history and price alert
Do you need price history chart (for all/most countries) for Excelvan Q2 Kids Toy Projector Blue? There we go.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).