[G-CPTN]

OK, so now we have more information about the fault (air servo leaking - suspect perished diaphragm, master cylinder leaking - old anyway) you need to start a search for parts for an EJM - either new or reconditioned (or even from a scrapper if 'guaranteed').

I'll see if I can find what you need (on the basis that I will provide links that I can find rather than me actually verifying if the parts are correct!).

I presume that your vehicle is right-hand drive? If not then you might need different parts (or maybe the mounting brackets allow for that) - worth checking with the supplier who should know more than me.

Describe your vehicle as a TK EJM 1977 (?) to provide as much information as you have for the supplier to ensure you get the correct parts.

If you cannot find assemblies, then you might find seal sets are your answer (even with the extra labour cost - the actual work isn't difficult and should be well within the capability of any 'mechanic'). I agree that assemblies removes the possibility of further complications, but I can reproduce the instructions from my MK manual which will explain what is needed to be done. I'll see whether I can get my scanner to work (it's actually the printer bit which isn't printing) or I might buy a new printer (actually cheaper than buying ink cartridges!).