If you could possess any simple movie prop (and not the thing it is supposed to represent on screen), what one thing would you like to have? For me, it would be a particular racing trophy from a particular movie. 
I’m sure you are referring to the Gumball Rally.
For me it’s The Neverending Story book. You can get pretty decent fan made versions of it on Etsy, though, so I probably should look into that.
Does clothing count? Some actors have worn some nice outfits I would like to keep or wear - well, maybe just keep as a memento, like some suits.
Sam’s piano from Casablanca. It’s a little big, though, so I’ll be happy to settle for the Maltese Falcon, from The Maltese Falcon, of course.
David Suchet’s Poirot’s swan headed came. It seems I could buy a replica. If I actually start using a cane, I might get one.
Theoden’s armour.
Indiana Jones’ whip.
The Necronomicon Ex-Mortis.
Otto from Airplane!.
I hope so. I’d like to have the Howard silks from Seabiscuit.
The Book Of Enlightenment, from Circle Of Iron!
Mary Poppins’ umbrella and carpet bag.
The Clark Nova typewriter from Naked Lunch.
The murder weapon from A Clockwork Orange. Yes, I am a filthy old soomka!
Does TV count? An actual TOS tricorder. I love classic 23rd century design!
If it must be a movie, Luke’s lightsaber.
Star Trek Medical Tricorder
Outfits count, tv items don’t, and you must pick Mary Poppins carpetbag or her umbrella.
And I’m sure you are correct.
Jude Law bowler in Sherlock Holmes
If I can only have one, gotta go with the famous parrot-headed umbrella, then.