In the 'good old days' when you could contact M directly, I contacted them to see if I could buy a couple of G series boxes from them as my original boxes had been damaged in the loft by water when some roof tiles had shifted and to M's credit, they sent me 4 brand new boxes with the 'rubberised' internal packaging and I still have 2 of them, which following a house move about 3 years ago, I no longer need them.
They measure 10 inches H x 21inches W x 25 inches L and were sent to me in 2006.
If any fellow HH'r would like them, they're yours, FREE OF CHARGE for collection from the St Albans, Herts area.
If necessary, they could be couriered (UK Mainland only !) and obviously they don't weigh very much, but are quite large and you would need to organise and pay the courier charge - I have no idea what that would be, but presumably, not a lot and could be quite valuable if you own G series kit and don't have boxes, or they're in poor condition, plus they could of course be used for other M kit (excluding 800 series I think).
So, if anyone is interested, please PM me - first come, first served !
Regards
Steve