Thanks. Do you think the 4-65 stamp is the date it was made? I have tried to search for PF151 but found nothing regarding who made it etc.My guess is a power transformer supplying 350 volts AC, possibly a 6.3v and 5v heater tapping.
Without the core size and winding diameter a guess at the wattage cannot be acheived.
Edit; If the core size is around 1" then expect about 100V/A
50V/A HT and 50V/A heaters