not sure if this is your thing but we've got eleanor this in 9 - 12 months for a wedding next month and i think it's going to be too big
http://www.next.co.uk/shopping/children/newborn/12/8
there's a matching hat as well.
M&S have a few nice things too for examplet
http://www.marksandspencer.com/gp/product/B001OM3HR6/sr=1-4/qid=1241554452/ref=sr_1_4/278-0122123-7672805?ie=UTF8&node=46402031&m=A2BO0OYVBKIQJM&keywords=&mnSBrand=core&size=9&rh=&page=
but i'm not sure this is your thing so i hope you're not offended at the suggestion.
I can't think off the top of my head whether i have anything suitable in the loft that you could borrow or have in that size. If i think of anything I'll let you know.