BENGHAZI, Libya, Aug 15 (Reuters) - Libya's internationally recognised government has appointed Naji al-Maghrabi as chairman of its state oil firm NOC based in the east of the country, an oil official said on Saturday.

The move is largely symbolic as oil production and the marketing of exports are controlled by the established state oil firm, also known as NOC, in Tripoli where a rival government is in charge.

The official government has been based in the east since losing the capital to the rival administration a year ago. It has appointed a head for an oil firm NOC based in a separate headquarters in the east but oil customers have refused to deal with it, preferring to pay through existing channels via NOC in Tripoli.

Maghrabi, who is currently in Egypt, will replace al-Mabrook Bou Seif as chairman of NOC in the east, an oil official said, without giving a reason.

The official cabinet of Prime Minister Abdullah al-Thinni has struggled to make an impact, working out of hotels and rented villas in the remote eastern city of Bayda.

Ministries and key state bodies such as the state oil firm or the central bank are in Tripoli, which is controlled by the rival faction, part of the turmoil in the OPEC member four years after the ousting of Muammar Gaddafi.

Oil insiders say Thinni's new oil company had contacted prospective buyers via middlemen and firms in the Gulf region earlier this year but legal concerns over ownership of the oil, given the duel governments, prevented any deal.

(Reporting by Ayman al-Warfalli; Writing by Ulf Laessing, editing by David Evans) ((ulf.laessing@thomsonreuters.com; follow me on twitter @ulflaessing; Reuters Messaging: ulf.laessing.reuters.com@reuters.net))

Keywords: LIBYA OIL/