This is a black rubber chop reading
遼西地區
West Liaoning Prefecture. The issue date
is thought to be 15th September 1945 (and I have seen an example
dating 18th September 1945).
Kerr felt that
the status of this chop was questionable.
These stamps have been identified by
using the four booklet guide
The Local Overprinted Stamps of Manchuria 1945-7 by Allen D Kerr
(published 1978 and now out of print).