Originally posted by 851korho would any Nikon/Canon DSLR case do
Unfortunately those will not work. A Pentax camera will melt down into a blob of embarrassed sludge if you put it into a Canon or Nikon bag. I've been told if you put it into a Sony bag there is a change of spontaneous combustion.
More seriously what type of bag are you looking for? Backpack, sling, shoulder, or holster? It depends on what you want to carry along with the camera. Go to the Lowepro site and use their bag selector to get an idea of what is available. I use a Lowepro sling bag 200AW.