Alternative 3d molding techniques at home
Forming kinda blister out of paper is possible but not the way it's formed out of plastic. Paper is not elastic, it's bendable but not strechable. It's the issue of how cellulose fibers are formed and how are they entangled. 

Anyway - you can create a form out of wet mixed paper pulp. Wrap it around your model and then wait until it's dry. It will form amazingly stiff form. You can do it also out of wet handkerchiefs.

You could build a vacuum machine as in the formbox to squeeze the paper pulp the get water out of the material but the cover should be done out of light silicone film so it would be treated by vacuum.