71 CB175 with original horn. It only works a little while hitting is with a rubber mallet while holding the button down. I am ready to upgrade to something louder if I can figure out what would bolt on easily in it's place.

i.e. Need to have 2 wire leads and a 10mm bolt coming out of the middle.

 

if you don't mind the horn you have, why not get another 71 CB175 horn? other than that, you could fab a bracket for any horn or have someone fab a bracket for you