By Sergio Sáiz | www.expansion.com | SEPI, the State organisation that holds public stakes in Spanish companies, could obtain between €700 million and €2.5 billion with the privatisation of the national postal group Correos. It will depend on the formula used to sell it. The case of Deutsche Post could be a model to imitate. Correos has a staff of around 62,000 people. This point, which could be an engine for employment in Spain,…