Working with that much, one could easily siphon off most of their solvent without touching the basified solution at the bottom and then just use a normal (500ml) size funnel to get the rest.  Nothing needs to be filtered finer than a kitchen strainer, so a vacuum funnel in not needed.  You need wide range pH papers, aquarium papers are for just a few points above and below neutral, but they really aren't necessary either. The STB teks go way beyond paper's or meter's ability to measure and with MHRB and an A/B, there is a pretty clear visual indicator.