Some years ago, but I think it may still be available, I got a single foam-lined aluminium case in Maplins.

Putting the gun straight across it just fits (mine's the '46, not the 46M, but the overall length is the same), it may be better to put the gun across diagonally?

http://i301.photobucket.com/albums/nn75/IainKD/01_1.jpg

http://i301.photobucket.com/albums/nn75/IainKD/02_1.jpg

Other than that, the case is much larger - deeper, certainly - than you need for a pistol, but you could always make extra cut-outs for accessories.

Iain