There are 3 Hiller OH-23C aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 1955 and 1973.
N252LG
1973 Hiller OH-23C
Big Lake, AK
N234SM
1955 Hiller OH-23C
Sussex, NJ
N92672
Hiller OH-23C
Covington, WA