Jogging bottoms for tall skinny boys

[Chrisinthemorning]

DS is 6 and very tall and slim. I need to replace his trackers and would prefer the elastic to hold a little rather than just being on the drawstring- more comfy and easier for loo trips.
So far I have tried M&S, Asda, Sainsbury’s and Next- if they are the right length they are too big around the waist.
Where to try next? Thank you

Primark joggers are ok for my very skinny DS.

Thank you for your reply. We have had Primark before but they do go bobbly, looking for better quality if possible.

We got some black m&s ones last year with a working drawstring that meant you could pull them in. I’ve replaced this in the past with elastic so can be just pulled on.
I have to just search every time I buy them as there seems to be little consistency to the sizing. Also, look in the girls department. Often they can be a little slimmer.