The issue of concealing a 5" 1911 as opposed to a 4" 1911 is moot. It is the length of the grip frame that is hardest to conceal, not the barrel length.
In other words, it is no harder to conceal a Government (5") sized pistol than it is to conceal a Commander (4") sized pistol; the frame size is the same. Bobtail the frame and it is somewhat easier to conceal.
A CCO pistol on the other hand, i.e. Officer's sized frame and Commander length barrel is a little easier to conceal as the frame is shorter.
I don't know of any new Commanders, CCO's, or Officer's pistol for $500.