They are from Maplins around £4. These ones I think but a different size - http://www.maplin.co.uk/abs-plastic-boxes-1689
They are not precut unfortunately but pretty easy with a Dremel or similar. If you look closely you can see where I lacked attention for a sec :)
They are not precut unfortunately but pretty easy with a Dremel or similar. If you look closely you can see where I lacked attention for a sec :)