Proxy with Paypal payment module during checkout

Hello, We have a Magento eCommerce website and we want to setup a PayPal payment module but we dont want PayPal to know that our payment flow is coming from this website. So we want to create some kind of proxy going to/from another website. So, basically, the client will be on our Magento website (A) but during the Paypal checkout he will be redirected to our Wordpress website (B) which will send him to Paypal to complete the payment. If the payment is successful he will be send back to the Wordpress website (B) where the order will be saved and then back the success page of the Magento website (A) where the order will be marked as complete. Therefore, it is important that all the variables {price, order number, ...) dont get lost so the order will be confirmed on the Website B and A if the payment is succesful. Our websites are working and ready to use so all you have to do is to modify coding during checkout in website A and B for this scenario to happen. Regards, ADN Trading