88' nautique maintenance

[thebayisok]

Hey people, I recently bought an 88 ski nautique 2001 and it is a little rough around the edges, its not that bad but a few things need to be fixed. I may be updating this as my need for knowledge grows.
1) The horn doesnt work. It isnt the switch and I have located the horn. Has anyone replaced their horn? Where can I buy a new one?
2) the speedo lines are clogged from being in the delta, where is the easiest place to clear them from?

Thanks