I am using the walbro pump. I bought the pump alone as the kit wasn't available in my country.
This pump is smaller than the VDO unit I have thus I need to make a rubber sleeve for the pump in order to fit the holder.
As for the pickup screen, you need to use the one that came with walbro as VDO or Bosch one will not fit. I have to use some plumbing teflon tapes to attach a Bosch pickup screen.