[Arok2092]

So I just started a new file after all my other's got corrupted and my friend told me about this really neat Glass Helmet called Fin Gleam which has Night Vision and Water Breathing enchantments on it. He said it can be found at all levels from 1 to whatever the highest known level is. Only thing is the only website I found describing it's location isn't detailed enough and as it's underwater I need to know exact location so I can find the helmet faster. Does anyone know the precise game location or a website that has the location so I can find it? I am playing on Xbox 360 incase that means anything at all.

Any help would be greatly appreciated!