You would have to think of an idea to get them in then get them out without them getting deleted.
Rofl Hej. I would think you'd know damn well that only SC items get deleted when a player leaves the game (though all items are deleted when the game ends). There is proof of this from a fairly old SC bug where players used Niles to note stealing creation items inside the game and then bring them outside, unnote them, and use them (before Jagex area based them). This means that SC doesn't notice noted items or any non-SC item.
You would need one CFT to get out of the game, and one to get in(or a double LIFT)
So this would be almost IMPOSSIBLE to set up, but a 100% safe method of xfering.