Other than having a friend gift it to you, the only other way is to complete the "Break Into the Armory" job which is a job in the Underboss Tier because it's available as a loot drop item via that job only.
In the underboss job tier (lvl 60-99), do the job named "Break into the armory" for a chance to loot a multi-purpose truck. However they are very hard to come by. Do "Break into the Armory" for a...