There's a recently rebuilt Zenith 28if v05083a - which is standard for my 1108cc F6 on my crashed van, soon to be available on salvage auction (see page: https://www.renault4.co.uk/forum/threads/renault-4-accident-on-the-road.9828/page-5 ). Also has the standard restrictor in the hose, in fact the whole engine is good except for the vacuum advance unit (a new one of which I have in the garage). The whole car is good except for the front body damage. Need a spare anyone?