Please, PLEASE help me find shoes for a wedding

[YippeeKiYayMakkaPakka]

I have a dress and have looked everywhere I can think of for shoes, but I can't find what I'm looking for.

Dress is here.

So I'm looking for sandals in blue or grey, or brown at a push. Comfortable and either flat or low/mid-heel. I can only find flip-flop-type, which are too casual, or sky-high heels, and nothing inbetween. Budget is up to £30 or £40 at most if they're something I could wear again. Size 5.

these in the blue or the white?

lower

Peeptoes or good ballet flats would be lovey, does it have to be sandals?

The wedding is abroad and it will be very hot, so ideally sandals, yes. I like those first ones in the white, unfortunately the size 5 is out of stock. Lower-heel ones good too, but will a T-bar make me look stumpy?

debenhams have them in a 5