Help Identifying Radio Component and Replacement Part
I read it as 47000 pF which would be 0.047 &mu;F. That's a pretty common value in tube type equipment. 

Yes, a 400V rating is reasonable. 

You should also check the power supply filter cap. That is the tall round can. It most likely has either 2 or 3 sections internally, each with its own connection. The can is the common negative terminal.