A bit of info from the Bendix catalogue:
DB549, listed for 240/260:
https://www.bendix.com.au/catalogue/10727
DB1173, listed for '86-'93 240:
https://www.bendix.com.au/catalogue/10728
It doesn't give dimensions like their paper catalogues used to, but the pictures appear to show the same backing plate, with a slightly differently shaped friction surface. Both should be interchangeable.
No distinction between solid or vented rotors is given for any 240 pads in their catalogue, I'm pretty certain solid/vented Girling calipers take the same pads.
This is the ATE pad, DB62, same as 164:
https://www.bendix.com.au/catalogue/10729
It has a smaller surface area as far as I can tell, I personally think the Girling calipers are the better ones to have.