recording photo frame mod to mini amp/speakers

I bought a little recording photo frame at Walmart tonight for $2.88. Sadly someone had been testing it and the batteries are dead, so I can't check the volume til I can get new ones. What I'm wondering is whether anyone had altered one of these or something similar to make it mini amp w/speaker. I'm wanting to install something like this in some small stringed instruments(dulcimers) I'm making that don;t have much volume on their own. I've looked at all the altoid ideas and mini amps and mini speakers, but didn't see anything that would do what I need. Most were just for ipods. I did see one that used a spy ear and that's what gave me the idea for this. I have one of the cheap little clear plastic spy ears somewhere, but couldn't find it tonight I would be ok for picking up the sound, but I don;t think mounting the earphones on the instrument would give enough sound. The soundbox on my larger. dulcimers did ampllfy some earphones I got at Dollar Tree, but not much. I would add pics of the circuit board of this recorder, but my camera is dead. I would really appreciate any help with this. I need to keep the cost down as much as possible in order to keep the dulcimers affordable. The ones I am making are more a novelty item, so I can't price them too high.