Lava is to each owner, what they hold close to them. Kinda like borrowing your buddies balls. You just don't ask. I would lend an ear, or a piece of gear, before parting with my Lava Lamp.
That said, I found one at a thrift store for $2 once. Obviously, the original owner had lost his balls in a horrible divorce, and she just gave them away in spite. NOT cool!
By the way, if a ball-lees owner of an original mini 12" 'blue/orange' Lava Lamp, in the Denver area, comes forward missing his balls, I will gladly return it to him, without charge, or shipping costs. You need yer Lava Lamp dood. I feel for ya man.....
Jimmy