I want to make this - how? OG-107 military trousers

How to make this pants?

I cant find any sewing patterns online, the trousers itself is sold out.

https://therealmccoys.com/products/camouflage-civilian-shorts-mitchell-pattern_160-green?variant=43618201927938

Some fun facts: Its a classic military pants from 60s that was worn by anti-war protestants. The so called "Mitchell pattern" was created by the graphical artist/soldier Meldon Mitchell.

Thanks for your advice on how to generate this trousers. The sewing process isnt a problem, just the approach towards the pattern.