Can't find any anywere was gonna float candles in them for centre pieces so they need to have sides and quite a large opening
I haven't seen any either. Have you thought about making your own? You could spray paint the clear floating candle dishes.
Krylon used to make stained glass spray paint (but I couldn't locate a link for it) but I did find this new metallic spray paint that comes in purple. Spray the outside of your glass, not the inside where the water will be :)
Design Master also makes sprays that are more transparent and would look like stained glass.