It’s a ’62 or ’63, it says here. Bore/stroke 2×1.5, approx 9.4 cu in, same as the Oliver 5.5 and 6-hp, and probably very similar to the earlier Chris-craft 5.5. Book says it weighs 40 lbs. As already mentioned, these are ‘improved’ Olivers, And I’d surmise the Oliver ignition parts would work.