What size brakes?

The rears I think are correct
As to the fronts ,the backing plate determines the shoe size. If the wheel cylinder push pins line up on the assembled system, without running at an angle relative to the car's centerline; then they are the correct shoe for the plate. And if the drum does not rub on the backing plate,or anything else, after it is properly installed and adjusted, then it too should be correct.
It is possible to install wrong,wider linings on the plate, but the pins will run on an angle.
It is possible to install too-narrow drum on the spindle, but the shoes will stick out the backside.
It is might be possible to install a too-wide drum on there, which as long as it does not rub on anything, at any time, should not matter.
I am not familiar with the early A's, but as far as I know, there was only one width front 10 inch drum ever fitted to our 67 to 72 A's.