create woocommerce extension

My client requires to be able to use multiple currencies on their wordpress install using woocommerce this is not possible. I have attached an image of a woocommerce extension I need making to make this happen. I am open to suggestions and ideas about how it should work so please ask if you have any questions. My client uses a woocommerce subscription extension plugin so this multi currency extension will need to work with woocommerce extensions also. Any questions please ask, start your bid with multi currency extension so I know you read and understood this thanks