Another trip to the JY has yielded results. This time I found a very good brake booster off a 2.8 TD Pajero that someone had already removed the master cylinder from. Only difference between the turbo diesel brake booster and a regular unit is a vacuum sender switch fitted to it. My previous trip was a bust due to me removing a brake booster that didn't have a spacer behind it (the mounting studs were way too short) but the master cylinder was probably the best one I could find in the yard. I abandoned it at the gates but it made it's way to the salvage bins where I put it through round 2 and bolted it to the second booster (finally got it right this time!). On the way out of the yard I decided to find a seatbelt warning light out of an old Volvo that I might be able to rig up in conjunction with the Peugeot seats. I liked the big, chunky look of the warning light bezel and Gen 1's are pretty spartan on the safety stuff.

I got my haul home, looked over what I needed to do to make it go together and cleaned up the brake booster assembly. This wasn't a bargain like the windscreen but the discount I got from the last visit made it reasonable and I did eventually get exactly what I wanted - $83 AUD (I had to get a new cab overhead valet light for the Hung Dog as the wagon had been broken into and some a-hole damaged it while trying to find a viable light source to burrow through all of the garbage on the floor). I picked up a 9mm high speed drill bit so I could make the necessary mods to fit the brake booster (the lower mounting holes are about 10 mm further away). I swapped the pedal yoke from the original brake booster (the new boosters' pedal yoke is shorter) and I used the booster firewall spacer as a drill guide. I had to adjust the pedal yoke so the pedal had a little free play and bent the crap out of the stock solid lines to make them fit as the rear brake line out on the master cylinder is facing the wrong way and the booster is wider and thicker. The only thing I need to address now is the brake level warning sender which is actually in the side of the single reservoir tank and the wiring from the harness is not long enough to reach. So now the 'guts' of the braking system has been fully upgraded. The new booster just fits with a few mm to spare (overall width is approx 220mm) and the 2 separate brake reservoirs have been replaced by one single standard reservoir. The master cylinder body is alloy with a 15/16" bore which should be ok with the twin piston fronts I've got waiting.
I feel like I've finally made some progress - all I need to do now is post the pictures or it didn't happen