I think we are half way to finding out which brake master cylinder to go for. John at Kit-fit Newark (very knowledgable about Fords) has identified it is Bendix, and not Lucas Girling, by the fact that the hole centres are on a 70mm pcd, and the studs are 8mm not 10mm.
So you need to be looking for a bendix m/c.
Have a look at this site - for reference only, as the prices seem horrific! The master cylinder I have looks like this one:
Note two pipes exit to the left (to wards the engine), and the third exits vertically downwards: this is for a Right Hand Drive vehicle. Whilst this is not essential, exiting to the engine will avoid the issues GOO had with them exiting to the side panel,(his is originally for a Left hand Drive vehicle). He has a remote reservoir, and was able to rotate the m/c so that his pipes missed the side panel. For those of you wishing to fit a reservoir directly to the m/c, it has to sit horizontally, therefore the pipes must exit towards the engine. (There is one which exits vertically down).
John is going to make a few phone calls tomorrow to see if he can source this specification m/c, and see what price he can come up with. I'll let you know what he comes back with.
Regards
Mike