OREANDA-NEWS.    PT Pertamina Irak Eksplorasi Produksi, a unit of state oil and gas firm PT Pertamina, has finalized a deal to buy 10 percent shares in Exxon Mobil Iraq Limited in West Qurna-1 block, Iraq, which currently produces 500,000 barrels of oil per day. The block is estimated to have oil reserves of about 9 billion barrels.