Vintage Synth Repair

Hi, group.

I've finally completed my System 100 by acquiring the mixer and
speakers from Australia.  Can anyone give me some guidance on
replacing the power cord/transformer to make the mixer function at
120V (from 240V)?  It would also be helpful to have the service
manuals for all the modules if anybody can recommend a source that's
reasonably priced/free!

Thanks,
Stephen