"Customised micro-motor gear box assemblies". .??
Has the MMMRRCo opened up a mechanical R&D shop ? Sounds intriguing. That 'orrible green army thing looks useful, throw the body shell away and you've got a handy sized two truck power unit.
Baldwin did a handsome 2-6-0 NG pannier tank for WW trench use; I don't know their catalogue code but if you Google "Snailbeach District Railway" you will see some photos of one on a mining railway. There's even a side view drawing of one somewhere on't tinternet. Would make a good Mogul based 35:1 mine loco.
Mince pies & mulled wine, Michael