Source for horn roller/contact?

[73-se]

I'm wondering if there's a replacement for this roller/contact in the steering column? Mine broke and I managed to fix it temporarily, but its days are numbered. I've got to get this replaced pretty soon. Does anybody know where to get these parts? I haven't been able to find them at the usual places. Thanks!

[Highway by the Sea]

I think that I need one too, because my horn works sporadically and a mechanic told me that I need a new horn ring (whatever the hell that is).  If you find a source I would also like to know!

[Nacho-RT74]

yes there is replacement... new switch 

or home made roller

Horn ring, maybe is the track down wheel/adapter where the roller works