Aren't there tons of good ones in Karachi? I went to Cistre and was very happy (they do heavier makeup than Bina Khan, but I think it has a similar way of enhancing your own natural beauty, just with a bit more glamor), but I know that there are even bigger names there. Search for bridal make up in Karachi. There are a few different threads.
Okay I have a really horrible sounding but possibly a successful idea.
Tell her that your engagement got cancelled for whatever heart-breaking reason you can come up with and ask her if a refund would be possible.