Ariel Schlesinger put together a guide on how to fabricate a cheap, homemade version of the wall-mounted CD player Nato Fukasawa designed for Muji.
Per Ariel's directions, here's everything you need:
a CD-player with an access to the batteries compartment from the front (disc side),
a pair of portable speakers that have a built in amplifier,
a pull cord light switch with a cotton thread,
circle cutting knife. for nice circle cuts.
epoxy glue, cardboard glue and some wires.
Or you could buy the original for $178.