Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Coupon (37.14 USD): BGWT15
(CouponsFromChina.com tip: coupon code has to be applied in shop’s 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): BGGines, BGc554f8, BG42759, BGc3f844, BG02cf64, BG2fdbaf, BGe0c811, BG35ca35, BGa0b557, BGc8412f, BG6e29ba, BGVEIKO
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for VEIKO 2PCS Quick Adjust Screw Handle Track Saw Rail Clamps is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).