Well you said Germany so this is Operation Varsity I assume based on the fact the first picture is a modification plate from a Horsa Mk.II
The modification plate is from a wing flap manufactured by William Lawrence & Co. of Nottingham (WLN). Unfortunately you can't tie it to a specific Horsa as all the parts were interchangeable with only the centre fuselage section owning the aircraft serial. The 3121 is the manufacturers serial for the part.
The mod numbers are for things like adding drainage holes, operational camouflage and markings and some specific to adjusting the trim on the flap.
Second pic - 5C/936 is a three-way downward identification lamp selector switch - so I think you've got the smashed up internals there. However, it's not off a Horsa - they weren't fitted with downward identification lights (they were swapped out for upward) and no such switch exists in the circuit diagram. So short of a better answer, its off another aircraft.
Third pic is just a standard pnuematic pipe coupling which was common on lots of aircraft but yes, this could be off a Horsa. You've got the inspection stamp and what appears to be part of a Dunlop part number (AHO422?). There were several manufacturers who made these all to a standard design.