I have had this and sucessfully repaired.

I used o rings BS016 vit75 (outer) and BS204 VIT75 (inner).

These supplied by M Barnwell services Ltd Birmingham B67 5AS.

Not only was the leakage stopped but a long term poor starting problem fixed, presumably due to aire in the fule.

The star washer is extreemly tight, I managed to lift one lug by screwing a small self tap under one lug, freeing it and then prizing it out.

damage to the bore is likly getting it out. this must be smoothed before a new ring is fitted.

I ground down the inner ring of the star to half width, to make it easire if i needed to get it out again. it still required a fair shove to get it back in.

the whole repair carried out with only battery and air cleaned pipe removed.