Silver would look gorgeous with purple. Although open-toe is a very popular style (I also dislike it) you should still be able to find many options in this colour that are closed toe. Not sure on your heel height preferences, but these ones from Debenhams are nice For a small heel option, these kitten heels are cute and will have you dancing all night! These ones are so glamorous with the chain detail but might not be noticed if your dress is very long! If you can't find any closed-toe silver shoes that you like, then you can never go wrong with a classic black heel.
silver with sparkle of coarse or a nude
Gold sparkled heels
The best decision my boyfriend and I made for my prom shoes was buy heels to arrive in and sandals for dancing. I had a silver sequin dress and my shoes were sparkly spike heels and white sandals. Highly recommend sandals.
I would choose a pair of clear platform shoes.