Best caliber for situation described.
Geeez , this is starting to sound like mission impossible!! Get a bazooka!! How about the side mirror mounted windshield washer with mace? Really with some of these scenarios are here-say, with Kevlar and body armor anyway. May be good for you, but look alittle obvious.And the calipers just keep getting bigger and meaner. If someone sticks a gun in your face you give up the goods, if they think your armed too, you're dead! Period! How about a different line of work or brinks?
Sounds like your already doing everything within reason anyway.
Sent from iPhone