Pack of 10 clear page protectors with pockets by We R Memory Keepers. 
I've been trying to find more page protectors to fit inside A4 ringbinders and these will do with a bit of custom hole making, I've added a photo with one overlaying an A4 lever arch ringbinder for you to see the sizing and the hole placement, (not all A4 binders are the same size so ask if you'd like me to measure them against your sizing, these are ones from WHSmiths and they're 32cm tall). The pockets are two 15x10cm pockets and one 12x21.6cm pocket across the top on both sides.