FLORENCE, Italy (Reuters) -Unions at Monte dei Paschi di Siena on Tuesday said 4,125 employees of the state-owned bank had come forward to take up an early exit scheme. Monte dei Paschi (MPS) aims to launch a new share issue later this month for up to 2.5 billion euros ($2.5 billion) to fund the staff exits and lower its cost base from next year. The unions said in a note that 4,015 requests related to an early retirement option which will see staff receive 80% of their salary for up to seven years before they reach the pension age. [nL8N2ZG3GZ] MPS will take a few days to examine the requests…