Spare gears for an Instant Fisherman reel?

So, as I've posted here a while ago, I got this Instant Fisherman rod from my grandfather. I wanted to have it ready for fishing, and one of it's problems is that the line wouldn't come of smoothly, making casting extremely difficult and limited. My solution to this was to let all of the line out, and respool it with slight tension, which fixed the casting problem. It now casts really smooth and easily. The thing is that by solving the casting problem I uncovered a new problem. The gears are shot… It was sliding when I reeled in, so I thought maybe opening it up to se what's under there would help. The smaller gear is really worn out, making it hard for the larger one to grip it. I'd like to get this fixed if possible, specially since it looks like such a simple task, bad gear out, good gear in, done. But I have no idea where I could look to find these parts for this specific reel, and also even though it looks super simple in theory, I'm terrified to tear the thing down and not be able to put it back together, since I've never disassembled any reel. What's your advice? Let it sit as is and as a memoir and cool but unusable item? Or try my hand at fixing it (if there are even parts available)?