C15 Headlight

[Liendrof]

Hi
I am new to this forum and motorcycle's
Recently I purchased a 1967 C15S, the dating certificate has it built in November 1965 and first registered in 1967.
However the headlight shell and the top of the forks are of the C15 Sportsman design.
My question is, Being manufactured in late 1965 it would be one of the last C15S's to be built, is it likely that there was a shortage of headlights and the Sportsman headlight was fitted or has it been fitted at a later date.