A lot of people on here use plastikote water based enamel (little pots - you brush it on). It is accepted as pet safe. It's the only one I would use on things for a hamster. It does come in a range of colours, although not that huge a range, as well as clear. I don't know much about childrens water based paints, but I think not all are equal. This is the range of plastikote - it also has the advantage of being wipe clean and waterproof ish - up to a degree. The spray on one isn't suitable. Don't know why the link to ebay seller says "Access Denied" but it's fine if you click on it
Lots of places sell it - that's just to show the colour range. Amazon sells it (usually market place sellers) and our local hardware store sells it.
Access Denied
I did the shelf in our hamster cage in garden green. It can have a slight shine or look more matt, depending on what you paint it on. For example the shelf (far end in cage) had previously been painted with clear plastikote so has a slight shine on it. The roof of the house (front of photo in cage) just has one coat on plain plywood and is more like a matt colourwash. Looks like this
