Get a tape measure and just measure the width - height and depth are standard - width is usually 600mm (23.6")
Slimline appliances are typically 450mm wide (17.7")
If you don't have a tape measure use a piece of string and take it with you to the store.
In the UK Comet will deliver next day if they have it at their depot and you order before 13:00
Peccavi
November 2009