Always endeavour to offer a design type with Chinese stamps, if you have a catalogue.
Sc# Type A57
686 1946 $300 on 10c surcharge Dr. Sun Yat Sen
Stamp 5 has me stumped
Sc# Type A37
$500 on $30
Could be nth eastn provinces Sc#44 1947
but the top script does not seem to fit.
Puppet Govt of Nanking
Sc# 9N104 1944 $5 carmine rose
North Eastern Provinces
1948 Sc#J7 $10 on 10c surcharge