The quiver from the Montblanc accessory range, an Italian piece of leatherwork, takes even a 149 without difficulty, so a 146 sits in it with room to spare. Anyone looking for something sturdier than the flat cases is well served by it. The quiver was later dropped from the range and could be found for a while afterwards as residual stock at specialist dealers.
The Traveller case will take a 146 as well: it is cut for the 147, and that pen matches the 146 exactly in its dimensions. One widespread misunderstanding concerns the loops on the inside — they are meant solely for the Traveller's ink cartridges, not for writing instruments.
Since Montblanc has carried a whole series of different cases over the years, it is worth trying one at the dealer's with your own pen before buying; only then can you judge whether the pen sits firmly enough without jamming as it is drawn out or picking up scratch marks in time. In price the Montblanc cases are on a level with comparable makers — leather cases from Graf Faber-Castell, for instance, are no cheaper.