
tescos?
Depending on age/size (gie us a clue and might have more idea's. new look, MK one, other high street stores
Maybe try finding a pair of light trousers and a jacket of a different colour to go with or a nice, plain, knee lengh skirt.
Suit finding can be very hard for younger children as they don't wear them everyday. I know the hassle I had, luckily eing quite tall ment as a child I could fit in petit ranges (although looked abit silly on hips etc) It sometimes worked.