Calhon

its in aria company

the white one is rare sometimes, but you can skip the day until it spawn.

^ but there is a way to spawn it in singleplayer, then launch into mp to get it. I used to do it last year, but since then I forgot..

hmm there is a mod for it actualy, change all trailer list as that one.
but i dun have the link since not using any
you may want to check somewhere on Guides forum.