If you're a normal, or slightly slender side clothes can easily find at shops. Not enough dry clean cloth just visit any shop and get new ones.

I frequently do 1-2 weeks camping trip and at minimum 2 pairs in the backpack. 1 pair shirt + cargo pants that I wear and another 2 pair in the bag. Wash the cloth when you stop. Self serve laundry is everywhere. Or wash and rinse at the river.

I wear a new pair every night, sleep in it and entire day tomorrow. I don't sweat a lot at night so it's doable for me.