Is there a a marine case for Canon A530 ?

Answer 1

There's the offical Canon WP-DC2 underwater case (for the A530/A540) http://www.ritzcamera.com/product/441160074.htm ; there's alternative hard cases, such as this Ikelite: http://www.adorama.com/IK614054.html ; and there's a variety of preformed 'plastic bags', usually rated for depths up to 10 meters.
You shouldn't have a problem ordering something... but they are all expensive.