Well I popped into Maplin last night and got the bits for this. Box seems pretty close. Not bad for a quick attempt:-
They didn't have the chrome LED surrounds in stock, so I'm using a black plastic one painted silver for now. The box looks more square in the photos for some reason, but the sides are tapered quite a bit in the flesh. And yes, the LED does flash red
Going to have fun with this in the office today, just leaving it on my desk with the light flashing
John...