Nice flats for a wedding? I'm stumped! (Or stumpy)

[Skinheadmermaid]

I cannot walk in heels, any heel and alas i have been invited to a wedding. It seems my only choice is to buy a pair of embellished pumps but i can't find any that don't slip off my feet?!
I'm a size 7, any other size is too small but i guess my feet must be quite narrow. I'm wearing a navy dress if that helps, i'm size 10 and quite muscular.
Does anyone have any ideas? Otherwise i'll have to wear my trainers...

Without having any idea of the style of the dress, what about these?

I know you said no heels, but have you tried kitten heels? I struggle with heels but can just about do a day in kitten heels

These? Anything similar with an ankle strap or t-bar with buckle will look nice and won't slip off. I have narrow feet and can't wear normal ballet pumps at all.

Oh i really like the gold pumps. My only concern is i have very muscular calves and wouldn't the strap make my legs look chunky?

I'm probably wearing this dress by the way:
m.dorothyperkins.com/mt/www.dorothyperkins.com/en/dpuk/product/dresses-203543/fit-flare-dresses-204534/navy-bardot-dress-2561623?bi=49&ps=24
I have a big glittery necklace, a lot of big hair and a fair few colourful tattoos so i didn't want anything too embellished iyswim (incase you think ew thats so boring)
Plus navy is one of my best colours.
I was thinking black or gold shoes or red to match the flower in my hair? Or would i look like dorothy gale?

Those gold shoes are lovely! I wouldn't worry about the straps Skinhead, just don't do them up too tightly, I think the fact that there are two and they're delicate and almost skin coloured (sorry, maybe not!) will bake them blend in more than other ankle straps.