Try Porvair Filtration Group, they also make porous plastic like Porex, trade name is Vyon. It is regularly used in vacuum pads.
(US Sales Office)
454 South Anderson Road,
BTC 514, Rock Hill, SC 29730
USA
T: +1 803 327 5008
F: +1 803 327 1052
or
Wrexham, UK
T: +44 1978 661144
F: +44 1978...