Don't be so certain that the Bren was a DeWat. Following the motorbike crash that took the life of Thomas Edward Lawrence, AKA *Lawrence of Arabia*, the executors of his estate found a number of lovely trophies from his service at his cottage at Cloud's Hill, including a perfectly servicable Lewis Gun with several drums of ammo for it.
His S.M.L.E. rifle- with five notches in the stock- resides in the Imperial War Museum collection, following Lawrence's presentation of it to Britain's King George V.
Nowadays, of course, you would get a minimum of 5 years and probably more like 10 years in prison for mere possession of a fully-automatic weapon and you can be sure that the cops would have had those two guns checked out to make sure that they were deactivated.