First, as has been mentioned, forget the permit. Even [i]IF[/i] you could get one, they are highly cost-prohibitive, with firearms storage requirements second only to Fort Knox, not to mention the high cost of the permit itself.
Second, Troy is right about the movie gun rental business. Stembridge liquidated their inventory as a direct consequence of a Caliban edict that made it illegal to sell machine guns [i]out of state![/i] Stembridge couldn't sell them in state or out of state, so what was he to do with them? He saw the potential for his collection to become worthless, so he sold most of his stuff on Bower's board, and some of the collectibles like guns used by John Wayne, Errol Flynn, etal, were sold privately.
Stembridge could have gone to court but he saw the handwriting on the wall. Their demise was really a shame because they had been supplying guns to the movie business going all the way back to the silent movies in Charlie Chaplin's heyday.
Only one gun rental company stuck it out AFAIK and decided to go to court if they had to, but they were on the verge of going out of business about a year ago. They may have already gone under for all I know. It's remarkable how the TV and movie industry has all but abandoned California. What was once California's golden child is now California's bastard child. In fact, a few weeks ago Gray (RED) Davis announced a multi-billion dollar incentive (Hollywood welfare) package to get the entertainment industry to bring their dollars back to California.