There are 3 Travel Air L-4000 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 1929 and 1931.
N475W
1931 Travel Air L-4000
Columbia, MO
N390M
1929 Travel Air L-4000
Brookhaven, MS
N8132
1929 Travel Air L-4000
Nevada City, CA