HONG KONG/SINGAPORE (Reuters) -Hillhouse and Japan's Mitsui & Co have emerged as final bidders vying for Singapore-headquartered traditional Chinese medicine chain Eu Yan Sang International, in a deal that could fetch over $700 million, two people with knowledge of the matter said. Eu Yan Sang's shareholders, led by Singapore-based asset manager Tower Capital Asia, will conduct management presentations with the bidders next week, said one of the sources. A third bidder is also in the mix to buy Eu Yan Sang, according to one of the sources and a third person familiar with the transaction, but Reuters could not verify the identity.