Aliexpress
Click here… to search for Universal Double Side Warning Strobe Light Bar [EU] on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Europe 
. I don’t really know if this price is reasonable, coz there’s no price history in my DB. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (43.99 USD): BGSCM11
(CouponsFromChina.com tip: apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Price history and price alert
There is only one database record (it was for 43.99 USD), so you can’t see price history chart.
You can set price alert (for Banggood).