You might not find your dress on the first try. And that’s okay. Finsbury Park is the kind of place that rewards persistence. Go back. Try again.
And if you find a dress you love but it needs alterations? Most local shops have seamstresses nearby who are wizards. They can make anything fit like a glove.
So go on. Get yourself to Finsbury Park. Grab a coffee, a pastry, and prepare to say “Yes” to the dress. You’ve got this.