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 (37.94 USD): BGWDT15
(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): BGDRB18, BGGines, Tabby20, BG02cf64, BGWT15
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Drillpro Woodworking Profile Fence T-Track Slot Sliding Bracket 600mm.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).