After a continuous struggle and attempts to acquire Dresser-Rand Group Inc. (NYSE:DRC) for the last three years, Siemens AG (ADR) (OTCMKTS:SIEGY) might have to offer a record bid for the company. Siemens is ready to pay up to $80 for every share of the company, which will put market cap of Dresser-Rand Group Inc. (NYSE:DRC) at…