Absolutely could be 100% legit and you've got yourself a bargain. Do bare in mind though that a working servo doesn't equate to a working EXUP, Recently someone bought a Fazer where the valve had been removed and blanked off, with the cables tied up and hanging loose, the servo was still active and there was no 7000 speedo error code. A quick test ride should put your mind to rest though, the bike should pull smoothly from low revs with no noticeable jump in power, if it's lacking low end and takes off about 5.5k then the valve is either stuck open or has been removed. The other issue with the EXUP is that the housing bolts are prone to seize which is not always a straightforward fix, with the fairing fitted it will be difficult to make sure these are OK.