Ianchu

What about pixabay? I've used footage from there quite a number of times, and it's free. Also, at least as far as I know, you can even use most of the things from pixabay for commercial purposes...

Just post it here
 
Being a owner of this camera as long as the lens and internals is in good condition it will work great. Avoid the digital zoom, it's cancer.
 
I'm assuming you're going for the camera?
If so buy this: https://www.ebay.ca/itm/58-mm-58mm-Conversion-Tube-Lens-Adapter-For-Canon-S3-S5/401247651720 (don't panic about it being the last one or sold out, there are plenty on ebay and might find it locally, avoid the canon ones as if my memory serves they are PLASTIC and over priced). It gives you the ability to add filters and additional lenses Like my Raynox DCR-2025PRO. I wouldn't invest heavily into the camera (aka don't buy the lens i just mentioned) because as mentioned it is old. However a lot of the filters are good on various canon DSLR lenses.
 
Here are 2 pictures from the S5 (had a hard time trying to find them because it became my destroy toy after I got the SX40).
Use rechargeable AA batteries, because it will suck the alkaline ones dry fairly fast using flash...
 

This one might be up your ally. I am a fan of the Lumix series and you can get one used for around your price range. It is small and offers great image quality.
 
Panasonic-DMC-TZ81EG-K-Traveller

are you talking about filming with multiple cameras or just recording video and audio using separate devices.  either way if the cameras have a integrated mics you record a loud sound like a clap and also make sure the camera video sees the hands clapping.  and in the editing software you line those moments up like when the palms touch and the audio suddenly peaks or you can use a plugin like pluraleyes which will try to automatically line up the audio waveforms

Thanks for all your thoughts on this, i think i will stick with the camera i have, and just invest in some LED lighting. the camera model is listed in the original post, If you want to see some of the things we have done so far then have a look at https://www.youtube.com/channel/UCWFUiaRZdSBAhwfcJ3fakww  some of our work is not great but, with time we will get better !
 
let me know what you think and how we could improve the quality.
 
but yeah it is good fun, we both enjoy doing it which is the main reason as my son had been asking for months, i gave in, and i'm glad i did actually it's great fun, we are learning lots along the way which is great !

Before you venture into buying a new camera have you made sure you are shooting the best way? By that I mean checking focus, exposure, white balance, etc.. If you can dial in the settings you can get decent quality out of almost any camera.
 
If you got a couple of bucks I recommend this book. It is a really easy to read guide to video creation.
 
Good luck on the content! I hope to do the same with my son when he gets older.