Jim, in my SL Wear for music I used a similar dolls house wind up gramophone, for the sound, I used an iPod nano, I think it's called. I cut the ear buds off, keeping the control switch. I soldered the ends to both sides of a 6 watts per channel miniature audio amplifier chip from eBay ($3). Soldered 2x2" speakers to the outputs and powered the chip with a 4 cell receiver pack. It's quite loud enough. I'm dusting the launch off for The Mersey River Festival today so will get some pictures for you.
Your model looks really good and I'm looking forward to some videos. Well done.
Jerry.