UPDATE 1-Penn West to buy Endev Energy for C$125.5 mln

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OTTAWA, May 21 (Reuters) - Penn West Energy Trust (PWT_u.TO) (PWE.N) said on Wednesday it has agreed to acquire Endev Energy Inc ENE.TO in an all-stock deal that will add about 3,500 barrels of oil equivalent per day to its production base.

Penn West, Canada's biggest conventional oil and gas income trust, will exchange 0.041 of a trust unit for each Endev share. Based on May 20 closing prices, that equates to an offer of C$1.41 per Endev share and values the deal at about C$125.5 million ($128 million), according to Reuters data which lists Endev's share count at 88.9 million.

Penn West, which expects to issue 3.9 million trust units under the transaction, said the deal is worth approximately C$170 million including debt.

Based on the closing prices May 20, the arrangement yields a price of approximately C$49,000 per flowing barrel of oil equivalent, Penn West said.

Endev's current production is weighted approximately 78 percent to natural gas and 22 percent to light oil and natural gas liquids. Its primary property is near Majorville in southeast Alberta, near existing Penn West operations. ($1=$0.98 Canadian) (Reporting by Susan Taylor; Editing by Scott Anderson)