Just reporting back to say that the new points made a significant difference to performance, well worth fitting. The capacitor was fine, no perceptible leakage. The main problem was mechanical wear, with the moving contact arm having developed eccentricity on its shaft. The uncertainty in contact position was noticeable when compared to the new item. Starting is now easy, tick-over and high speed running smooth at a 15 thou gap. For reference, the package was marked as Meiki part FR64902; the parent company is Mitsubishi. Thanks again for the advice here - interesting to keep this machine going.