UPDATE 1-Tenon plans to buy RSM Bentley for up to 76.3 mln stg

* Says to raise 40 mln stg via share placing to fund deal

* Sees synergies of at least 6.3 mln stg

* Says may seek additional banking facilities (Adds details)

Dec 9 (Reuters) - British business adviser Tenon Group Plc (TNO.L) said on Wednesday it planned to acquire RSM Bentley Jennison, a UK-based professional services firm, for up to 76.3 million pounds ($124 million) to boost its geographical reach.

The company said it would raise 40 million pounds by placing about 88.9 million shares at 45 pence apiece and issue up to 47.8 million shares to help fund the proposed acquisition.

Tenon said it expected synergies of at least 6.3 million pounds from the deal.

The company said it might seek additional banking facilities from Lloyds TSB Bank (LLOY.L) to fund the acquisition, business integration and assist in further organic growth.

Tenon shares closed at 50.5 pence on Tuesday on the London Stock Exchange. ($1=.6155 Pound) (Reporting by Tresa Sherin Morera in Bangalore; Editing by Deepak Kannan)