Anyone else on the same mission may want to contact Johnny Bova in the US http://www.johnnysvintagemotorcycle.com/
I have not fitted it yet but he has supplied a new pattern one which he says is the same as the original twin disc conversion and it looks the part (with round reservoir not the trapezoid one on the A1/A2) - the only new option I could find on the Z Power site was square and looks very modern
I think the part number is 43015-018 (but do check this with him)
Hope this helps someone
