1980 Ford Falcon pings under moderate acceleration

1980 Ford Falcon XD 351 Cleveland mileage: 146,000. I've got a Ford Falcon Australian car but same set up as a F150 or similar Ford running a 351 Cleveland, mildly worked. The car has started to ping very badly with even moderate acceleration. Sparks seem fine, timing is spot on the carburetor could be running better, but it doesn't seem to be the problem. A few friends believe it is the distributor. Is there a particular part of the distributor, which would be causing the majority of the problem, or something, which I can replace myself? If not I'll have to get it overhauled, but that's pricey. Thanks.