I have 18 Years experience in creating eCommerce websites using Magento, Zen Cart, WooCommerce, osCommerce.
Beautiful responsive websites for any purpose. Integrated eCommerce if required.
SEO is about helping search engines put your content in front of the right customers. It is not something you can add-on at the end, it must be integrated into the website as it is built.
If nothing else will do then a custom design just for you can be written.