I have a few of these bren boxes, in varying states of repair. Some have been modified to accommodate the L7 GPMG by removing some of the internal fittings (nothing too hard to replace or repair).
This year at Beltring I did sell a couple in this state for £40 each.
I am in two minds as to what to do with the remaining boxes. I am thinking of using them as parts for reproduction No15 chests for the sniper rifles. but it looks like a costly way to get the right type of hasps.....
if there is anyone out there with the old type GPMG transit boxes ......... (I think... if memory serves ... they too were fitted with the same type of hasp)