Check this out:
Franzen Armloc II Pistol Case
This is a really versatile pistol case that locks with either a combination lock, cylinder lock, or both. It has a carry handle built in, and it comes with 2 mounting brackets - one for the bed frame for quick access to your SD weapon, and another for more permanent mount to a wall, car trunk, etc.
When you want to take the case with you, just unlock it & detach it from the mounting bracket via the thumbscrews below the padding.
This thing is thing is rock-solid too. Impossible to break in to (without power tools, anyway).
When mine isn't mounted to the bed frame, it's going with me to the range. This is a VERY high quality pistol case for less than $100.
(No, I don't work for the company. I'm an IT guy from Sacramento.)
Quote from product listing on seller's site: "meets all of the FAA requirements for Commercial Airliners."