What kind of top? Help needed.

I'd either hire a lovely long dress or find a gorgeous long sleeved top in a colour that really suits you with which you can wear a beautiful piece of jewellery. I'd wear the top with black trousers in a beautiful fabric like velvet or satin but if you want to wear your skirt, just make sure it balances with the top. Have a lovely evening and once you have got dressed forget about the clothes you are wearing but wear a smile!

Have a look at Zara. They have beautiful evening tops, and as you are only a size 10 Zara's clothing ought to fit you.

Personally, I love a tuxedo suit - I would be lost without mine.

I might be way off what you like here, but if my husband were wearing a formal dinner suit, I would try to match him with a blouse with some kind of detail like a bow or pleating. I'd cover up as much as possible, but sheer sleeves are nice.
I'd start with black, some examples here are Reiss, Next and I can't remember what. If that is too dark, then I'd move on to maybe cream or nude. Either way, a good camisole is de rigueur. You can add fine jewellery to dress it up. Have a great evening.

Sorry, my phone is rejecting two of the images at the moment.

I have no idea what people are wearing these days for the same reason as you! Have you thought about hiring an outfit?