Pardon the order of screenshots. So what is going on:
- Pattern provider pushes al required components into a barrel and locks itself until primary product is returned (paper)
- Laser node triggers a redstone signal when exact number of multiblock controllers is present
- That signal is sent to export bus which exports required paper on a pulse
- Meanwhile lase node moves items back into system for wireless access
Only caveat is that controller block must not be the last item in a pattern. Otherwise pattern provider will push new set of items as soon as previous ones are extracted and sensor card will not flicker and instead give continuous signal, which will not allow export bus to feed the "paper" back