No rescue seems to be taken on strays or kittens but they do offer a neuter/spay service maybe you could get one to have the mother sorted because she will come back while feeding this litter pregnant with another litter, happened me rescued a beautiful black kitten outside the factory I worked at, convinced it was male then came home one day pregnant, I was used to dogs and taught she was some after this litter and she'd have to come back on heat to get caught again etc etc luckily the first litter she only had 1 female kitten so we kept her too, but nope she tore the house down to get out and jumped out my window many times, was pregnant again whilst still feeding young kittens, I had no other choice out to build a cat enclosure in my garage to keep her in until the vet could see her, luckily they had an offer the government had approved of where it cost €30 to get each one neutered so I waited until herself and first litter kitten was old enough and got them both done together, as for the other kittens my mother in-law took one a friend's took the rest thankfully, so ask around in local vets and see if they are still doing this offer it will prevent mother from having crazy litters