Interspire Shopping Cart Customization

We're looking for someone familiar with Interspire's PHP shoppingcart who can skin it to tie into the look and feel of our main wordpress site at [login to view URL] The shopping Cart Version 4 is already installed and functioning at [login to view URL] but the theme is incompatible with IE8, so we've purchased the Upgrade software to bring it to version 5, but the upgrade will wipe out our custom design changes. The ideal candidate will install the upgrade and apply a theme (using the elements from WP) If interested, there is also the opportunity to help with some design changes to our main Wprd Press Site also.