What subreddit would have information on how to fix an old toy train for my son?

I recently received a box from my parents containing books and toys of my childhood. My son(2 years old), being a train fanatic, has taken to a plastic train that has 4 buttons for noises. I popped some new batteries in it and got nothing. Took it apart and found 2 wires leading to the speakers are disconnected from the board. I'm also assuming that there's supposed to be some sort of pressure buttons on top of the board. I'm not sure what I'm doing at all with this repair my hobby is woodworking, so any subreddits geared towards electrical repair would work I guess.