UPDATE 1-Terms set for Sompo's $4.7 bln takeover of Nipponkoa

* Sompo gets one share in holding firm for each share

* Nipponkoa gets 0.9 share in the firm for each share

* Deal values Nipponkoa at about $4.7 billion (Recasts, adds details)

TOKYO, July 29 (Reuters) - Sompo Japan Insurance 8755.T will take over smaller rival Nipponkoa Insurance 8754.T in a share swap valued at $4.7 billion, according to terms of the planned deal announced on Wednesday.

Sompo, Japan's third-largest non-life insurer, and No. 5 ranked Nipponkoa had said in March they would merge in April 2010 to cope with sluggish demand in the mature Japanese market, but had yet to set the terms of the deal. [ID:nT167706]

Under the agreement, Sompo shareholders will receive one share in a newly created holding firm for each of their shares, while Nipponkoa shareholders will get 0.9 share in the new company.

The terms will give Sompo Japan shareholders a 57 percent stake in the new company and value Nipponkoa at 445.9 billion yen ($4.7 billion), according to calculations by Reuters. ($1=94.64 Yen) (Reporting by Taiga Uranaka)