I know Tom has a pair of these (I don't), but from what I have seen this are almost unbeatable at the price.
Silverman's Classic Chinos - 'remake of the classic 1940s and 50s chino trousers'
https://www.silvermans.co.uk/collections/clothing/products/classic-chino-trousers?variant=4193742531
Vintage trousers. Search Etsy/Ebay for things like:
vtg pants 30 (30 being your waist size)
1960s slacks 30
vtg army pants 30
etc...
When you find a good one, get it copied. Or keep searching like a maniac like me.
Haha. Not a fan of the flapped pockets. I really can’t stray from O’Connell’s. Their twills are a nice weight, made well, have a great cut, they’ll hem and cuff for no added charge, plus there is a multitude of colors from which to choose. Not cheap, but worth it to me.