Small adult workwear brands or sites?

I have a friend who is 5' 7" but ~100lbs. Men's sizes don't go small enough, and women's sizes are weirdly fitting and the XS still too big. Carhart overalls, for example, have small child sizes but then a missing gap before adult sizes. Are there sites or brands that carry workwear for this sort of size? Maybe 26x32 pants? 26x30? Natural waist around 25". Asian men workwear sites or brands?