The washer jet hose just isn't right...

It's only a small annoyance but...

It appears that the previous owner of my car at some point has replaced the piece of pipe between the washer jets on the front windscreen. Ordinarily this probably wouldn't be an issue as all 'normal' washer jets do is squirt a stream at the windscreen but the fancy misting done by the Octavia's jets obviously requires a certain pressure within the system.

The piece of clear tube that has replaced the OEM pipe is obviously a larger internal diameter and therefore instead of that nice fine azimuth of mist, I get a sort of vague stream with some foam that doesn't make it's way up the windscreen unless I'm doing 60mph. Having spent the summer coping with it, the sudden onset of liquid sunshine means I now have half a clean windscreen and it isn't my side!

Does anyone know the internal diameter of the washer tube so that I might be able to find something suitable and regain the pressure in the system and finely mist my side of the windscreen too? Or better still, a part number?

Before anyone asks, I did buy new washer jets first and yes, I have tried swapping them round. They are all clear and the problem is still on the drivers side and because the pipe is clear I am very confident there isn't a blockage.