I'm rather suprised you can't find any along KT river/secondary jungle streams. Know of any locals in Pekan? There are still plenty of streams there which i'm sure have wild bettas. I've even caught some beautiful Harlequins. No point looking around for them during the Monsoon. Even hunters can tell you where there are jungle streams located. Maybe Kuala Lipis, Raub locals will yield some info.

Heen