Confession time. Mine has an aftermarket lever. I did especially go downstairs to look.
. . . But didn't check the spares box that would have the original.
Quick Google comes up with this.
https://www.enduropuro.it/shop/en/fr...s-txt-pro.html
I think mine is another brand so look around.
That being said, I also found this.
https://www.bike-parts-gasgas.com/ga...rts/BE25922018