Now, I just went and did what Walter suggested, which was to go down to WalMart (we actually called it "K-Mart" in those days) and buy a plastic briefcase designed for the transport of not one but two handguns. Said cases do seem to be a common item in the sporting goods section of these kinds of places, and they come with a ton of foam padding to snugly protect the contents. A perfect fit!
Plus, these cases have all kinds of screaming eagles and American flags embossed in the hard plastic on the outside, so if'n you live in a red state like I do you won't get too much trouble from the locals on your way to your free-jazz hootenanny...