I think all the pieces are there, but I don't have the box or instructions anymore so I can't check.  Made in 1979 so some of the plastic locating pegs / joints are getting brittle (x2 broke when I dismantled it) so I don't want to re-make and then dismantle it again just for photos.   In my opinion it needs to be made and left made, and if I were doing it myself I'd be using the odd dab of glue to make it really sturdy, the roof ridge apex joints have already been repaired .  I've laid it all out in the photos so that you can see how it all goes together .

Britains 1:32 4710 Milking Station:

Everything there, entry gate levers all working well, one hose valve has come away from it's milking churn (easily fixed)