<p>The pola back is simply attached with the screws holding the standard back; the standard back is swapped out for the pola back. Just peel up the leather, unscrew the standard back and attach the pola back, voila! I use a dedicated body.<br>
Fuji FP100c fits the pola back and is sold at B&H for about $9US per pack and is likely not too difficult to find around the planet.<br>
Fuji FP3000b high speed B&W also fits but has been discontinued and has limited availability of outdated packs at premium prices.<br>
I hope this helps, please feel encouraged to ask me anything else and I will help if I can, or help you find a source for the info you seek.</p>