A project to restart production called, "the Impossible Project" (the "p" on impossible is backward for some hip and trendy reason) is restarting production of integral and other Polaroid films, however the cost is still in the $2 to $3 per exposure range.
What is the cheapskate hipster to do? Well here is one idea.
In this Instructable, we will convert a Polaroid Spectra to operate with regular sheet film.
This modification will pretty much destroy your cameras ability to shoot regular Polaroid Spectra or Impossible Project Image film, so there is no turning back! Also, your camera will no longer be an instant camera! You will have to develop and print (or scan) the images yourself.
Step 1: Spectra Camera Overview
Spectra cameras had higher quality lenses and better overall fit and finish than other Polaroid cameras. The original Spectra came with quite a few photographic controls. Sadly, Polaroid winnowed those down with each successive Spectra camera model. The only real tick up in quality was the Spectra Pro...designed (and priced) for professionals.
Its always been expensive to shoot Polaroid film, but now that Polaroid has stopped production and future production will be a boutique film item its time for this camera to modify this camera to use cheaper film.