Hi Charli,
You can achive the same through Plant at abroad functionality,whcih you can manage as separate plant as well as profit center & assinged to parent company ,where you can able to sold the materials,purchase the material ,stock transfer between palnt ,maintain the assets. Please read mentioned whcih may helpful to you. I did the same for one of the client based at USA & plant at Canada.
http://wiki.sdn.sap.com/wiki/display/ERPFI/Plants+Abroad
See tax procedure may different based on country legal terms
Regards
Mani Kumar