Horn and dipper switch a10

[kanchanau]

Is this the original bsa a10 plunger 1952 horn and dipper switch ?

[CheeserBeezer]

I don't think so. I think they were usually attached to the lever stock and were a round chrome button and black lever. May vary according to year but the one you show is not original to the best of my knowledge.

[trevinoz]

Definitely not.
The dipper mounted on the left lever perch, the horn button on the right.
Horn button same type as cut out button but different mount.