It seems like it would be pretty easy to just have a step down transformer from 120VAC to 9VAC. Also wire up the 9VAC to a bridge rectifier to get 9VDC to then convert down to 5VDC with an LDO or buck regulator of proper current rating. It wouldn't be the cleanest power supply but the C64 board should have proper filtering for each rail.
Re:C64 / VIC20 / C128 PSU Open Sourced
by white-flame on Wednesday January 16, 2019 @07:30AM
(#18920221)
However, it is quite easy to pick up two standard wall warts of the right amperages, and reuse the old PSU's cable.
A lot of the new Commodore and Amiga Hardware being developed these days is open source, which is 100% a great thing, enabling us to keep these classic machines running for many years yet.