Hi all, obviously brand new to the forum. My cousin and I have been working on restoring an old mini trail bike. To be 100% honest I'm not confident it's a Bonham brand, it very well could be a Sherpa or some other random manufacture. I've installed a new engine in it which is working fine. The only issue I'm having is with the high/low gear box.
I'm attaching a picture of it which is not great I know, I'll get a better one after work. The gear box is the silver box above the rear tire. The box itself is working, but leaking what appears to be some type of gear lube at a quick rate. Anyone have an idea of the best way I could repair the leak or get parts for it? It's leaking on the flywheel side (opposite the picture). I appreciate any feedback!

I'm attaching a picture of it which is not great I know, I'll get a better one after work. The gear box is the silver box above the rear tire. The box itself is working, but leaking what appears to be some type of gear lube at a quick rate. Anyone have an idea of the best way I could repair the leak or get parts for it? It's leaking on the flywheel side (opposite the picture). I appreciate any feedback!