This project could work great with a second hand pair of computer speakers.
You will need:
Munny Dolls. (x2).
Hot Glue gun
Vacuum Former (ok, so you prob dont have one but you will need a case for the amp)
Step 1: Breaking things
The Amp circuit board should also be taken out if you are going to make another case to house it. If you can/want to use the existing box, then leave it all connected. In hindsight, I probably should have done that rather than go to all the effort of making a new case.