<Are you sure about this?  Most switching power supplies immediately
<rectify and filter the AC anyways, and it seems to me that a 170VDC
<(120*sqrt(2)) source would be okay in very many cases.

Yes, for that design at 120v it is doubled to about 300v and then 
switched.  This permits 230v operation without a design change(jumper 
only).

If you really wanted to run on batteries the supply puts out +5/+12/-12
and power-ok.  A 12v to those voltages switcher at about 140-160w
would do, less if the disks are omitted (rd53/54) eat about 32w! 

Allison