Engine oil change from 15w50 to a higher viscosity

I have a 2000 Mitsubishi Lancer CK2 with a 4g15 dohc 16 valve engine. I’ve been using Valvoline VR1 15w40 engine oil and recently noticed its burning a bit more oil than usual. The tailpipe is clean with no oil residue and there are no leaks and only a slight smoke on cold starts. So I Was thinking of moving to a higher viscosity oil.

The issue I have is that in Sri Lanka the next viscosity of Valvoline VR1 is 10w60 and there is a Valvoline DuraBlend 20w50. Would love to get your expertise on which viscosity I should go for in my next oil change.