dude, it ain't that kinda party...
being a 71 it should have the chrome ring with the "D" and a wolfsburg crest centre cap (castle). usually the D's are missing and people make do without it in PK. if your steering is in order (the bits that are left) then i'd suggest you just get the horn part (chrome) from the kabaria till you find a better example or import one from abroad.
there are many options, here are some ideas: CLICK HERE