Careful students of Doug's main site will have seen his Larger PSK, packed in an aluminum Wheatley Fly Box.
http://www.equipped.org/survlkit.htm#LARGEPERSONALI think this just became a whole lot easier and much less expensive. Wheatley just introduced their excellent light weight, perfectly sized fly boxes
without any interior fly clips, compartments etc.
These boxes are 3.5 times larger than an Altoids tin. It is 15.2 x 9.0 x 2.8 cm, (~380 mL volume). An Altoids tin is 9.3 x 5.8 x 2.0 cm, (~108 mL volume), assuming perfect rectangle for both.
This cost me $22 at a local fly shop, and they are available in several anodized colors.
I am probably going to set up a kit that can be opened as needed (ie not stuffed and taped shut) using this box.