The maglite holder is a Maglite ASXD021 Auto Clamps Skin for ASXD026E (2 Pieces). Its an American part but they crop up on ebay and Amazon in the UK. It was £7.25.
The Goodman handle was from a chap off TheDiveForum (TDF) , £16 but you can find them on ebay...
At the moment its attached with a couple of tie wrays until I can find some bolts.
The Maglite slips around in the holder preventing the users from turning the ring which has the magnet on! To get round this I double wrapped some dry suit rubber strips to grip it.. works well...
Some more pictures..