Aliexpress
Click here… to search for SOOCAS X1 Sonic Toothbrush on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (33.68 USD): bGhOnEy10
(CouponsFromChina.com tip: just apply this code in your cart 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): DTC717, NDC1, 59c904, 502C6B, vipupgrade8, TTxBG10, BGkonimbesin1, BG15%SP, BGSOOCASX1, BGCAS125, AFfbG10, BGSOOCASSEP, BGBFCR48, BGBINKUPON917, BGMIJIA917, BGCITYADS2019, BG917MIJIAX1, BGHOMEG12
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for SOOCAS X1 Sonic Toothbrush? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).