I have some you can buy if you like; most white, one striped. They are Gap, with drawstring at hem, good condition. Very sweet. CAT me if interested. Am going away on Wed... but if you've got until September maybe that's not a prob!
There's an enormous Boots near here so will have a look at lunchtime.
I wonder whether John Lewis might have them.
Spots, I may well take you up on your offer, but will probably be in touch after Wednesday. Would probably only want white as (a) they look really cute and (b) If this is a DS2 then he might not like pink .