将OpenCart集成到另一个网站

One of my partner has an OpenCart webshop (selling electronic products). She wants to start some kind of affiliate program. So broadly the goal is: all of the products (with categories) can be integrated to another website. Other features should be accessable too, like product filtering, registration, cart, pay, so basically the full register-login-order process.

The budget is quite low, so I'm searching the fastest way to achieve this need. If it's possible I don't want to install another instance of OpenCart, because flexibility and speed is important to my partner (and to the her potential partners).

Can someone give me a starting point? Some kind of module/extension maybe? I saw a tutorial video (OpenCart product feed), but if I understand it correctly it's 'just' a product feed, with this I cannot do product search/filter, buy from the base webshop etc..

Thank you.

Opencart has a built-in affiliate system that maybe useful. Opencart also provides an API that you can use although you probably need to extend it so that it suits your needs.