[The Philpott]

I have forgotten what the R denotes at the end of the serial number..someone will know.
What does the text on the battery cover read? I think the transformer traditionally goes in with wingnuts uppermost. (But you knew that!) Those copper oxide rectifiers are remarkably stable by and large, the 1947 one i have just used is good at mains voltage, and only loses about 300mV when shown 12vAC. The internal transformer is probably fine as well, but i find some of the low current terminations are easily knocked when working inside the meter.
Let us know how you get on, perhaps you could do a restoration thread.

Dave