Vintage Stromberg Carlson PA-10 PREAMPLIFIER, power supply?

For Sale- I got this unit with a Stromberg Carlson AU-36 tube amplifier. I tried to do some research on this but only came up with the info that the PA-10 was a preamplifier. This unit appears to be a large power supply of some kind and not a complete preamp as far as I can tell. I have not plugged it in or tested it. Shows some minor oxidation on outer cover, no apparent problems though. Heavy and high quality. There is also a relay in the unit.

Send your zip code for ship cost- should be between $12.95 and $29.95 if you are in the continental USA (Nov. 2012).