Does anywhere sell 100% cotton school trousers, apart from M&S?

[MegBusset]

DS1 needs cotton trousers for his eczema but M&S Skinkind ones are out of stock... Eczemaclothing.com have them but at £28 Anyone know where else I can find them?

I've been looking for ages and haven't found any yet.

I emailed M&S in July and they said they'd have stock in October but I check regularly and there's nothing yet.

I ended up getting 50% cotton ones from Tescos but they don't even have those now.

If the M&S ones come back in I'll be stocking up for next year too.