Just spoken to Rich at Clark (very helpful) , they only stock original Nissan Rear wiper water pump and they are a little pricy for me, £50 ish delivered. They have 2nd hand ones for around £15 plus shipping. Been told that these pumps have a short life span so I guess it's not really worth buying 2nd hand. I've been driving around without a working rear water pump since my ownership from last July, guess I'll just save the money for other Zeditus needs
Thanks scobie140!
I bought a secondhand rear washer pump from either Clark Motorsport or zmanalex (can't remember which) around 6 months ago & it's still working fine. So I wouldn't knock a secondhand one if you do decide you want to get it fixed.
After all my original one lasted 11 years and who knows how many times it got used over that time (thousands I'd guess) so my secondhand one could outlast the car for all I know.