** Shares of Pinnacle Investment Management rise as much as 4.3% to a record high of A$22.37

** Stock among top gainers in the benchmark index ; set for best session since late Oct - if current gains hold

** Investment manager says it has reached a deal to acquire stakes in two international asset management firms for a combined consideration of A$142.8 mln ($92.93 mln)

** Shares enter trading halt before announcement

** Co also announces A$400 mln equity raising at A$20.30 per share; says to use part of it to fund the acquisitions

** Morningstar raises its fair value estimate on stock to A$13.40 from A$12.30 on expected earnings upside from growing the new affiliates

** It, however, flags that shares remain overvalued

** Including day's moves, stock has more than doubled in value ($1 = 1.5366 Australian dollars)

(Reporting by Archishma Iyer)

((Archishma.Iyer@thomsonreuters.com;))