maybe get yourself a few basics n the UK and have a shopping spree once you get there. Much more fun and at least you'll find better choice in the right type of clothes instead of trawling the shops now desperately looking for something that ticks all the boxes.
and are you moving there or just going on holiday?
Coz if you are moving there you'll only need long suitable stuff when out in public, if you're going to ther people's houses the men and women are usually segregated so you can be more relaxed about what you wear.
But it really does depend on the country, so where are you going?