i just found out at your nearest local harborfreight you can buy an owoga horn for like $40 -Joe The Doo Wop Kid
Speedway offers a compact "ah-oo-gah" horn for 34.95 (that's what THEY call it. They also have a Chrome plated (plastic) bell "aa-oo-gah" horn for $49.95 that takes a $22.95 Painless relay. That's the one I got-quality is okay.
my sister has an "Ooga" horn on her '55 that she got from California Car Cover. sounds like shit tho.