Am I right in thinking that all road integrated headset bearings are the same?
nope
Do road bikes all have 1 1/8 steerers?
nope
Are there a million standards to navigate? Help!
yep, and in some ways it’s better than MTBs, others it’s worse.
The very best way to get the correct ones is either get detail off existing bearings (if you can see them) or measure.
I wouldn’t just rely on the headset model name as even they can have variations between years etc.
Dimensions you need are:
internal diameter of bearing
external diameter of bearing
height of bearing
angle of external seating
angle of internal seating
The internal and external angles are often the same, but not always, and be careful about the height, several times I’ve had to rescue people from a binding headset because they bought ones with the right angles and diameters but wrong height!