Wire clips are 'correct' almost certainly, but much inferior to jubilees. Any picture at a motor show may well have jubilee types, and any picture taken after a sensible owner had bought the car would have jubilees too.
The wire and nut type lead to a shorter life for hoses, but as they are cheaper, most car manufacturers were using them at the time. I very much doubt if Morgan were any different.
Tip - buy your stainless jubilee clips from a chandler. Often cheaper for these than a car parts shop as stainless prices are often loaded for cars; you'd not use anything other than stainless for a boat that might see salt water.
