ITEMS: switch 'standard' image for 'large'

Hi,

How to make the featured image in the upper left corner on an item page bigger?

in the upper left corner on each item page, there is the featured image.

Right now, it's small 300px.

For me, the images are arguably the most important and wish to make that part bigger.

However, if I resize it with CSS, it will look crappy as the underying image served by dozuki is actually 300px 'standard' size.

Any ideas?

How to make this image bigger and better?

Thanks.