Some China ID Help Please

After going through a few hundred of Chinese stamps and finding these in my Michel catalog I am left with the ones shown in the picture below. I just cannot seem to find them.
Any help appreciated!
Peter

Top row, left to right: overprinted for Taiwan; overprinted for Sinkiang/Xinjiang; unissued - looted from the printers in Hong Kong; Post Office Savings Bank stamp
Second row: Overprinted for Sinkiang/Xinjiang; postage due stamp; Post Office Savings Bank stamp; revenue stamp
Bottom row: Overprinted for Mengkiang/Mengjiang (Japanese Occupation); revenue stamp; revenue stamp; Post Office Savings Bank stamp

Thanks very much for your help!
What exactly are Post Office Savings Bank stamps?
Can they be found in stamp catalogs?

Peter

The Post Office Savings Bank stamps weren't postage stamps, and so they aren't listed in any of the postage stamp catalogues. I believe there are specialised catalogues that do list them, however.

They were for use in the Post Office Savings Bank. The Chinese Post Office reached deeper into the villages than any of the banks, it was considered to be more reliable than most of the private banks at the time, and it would accept very small deposits - probably smaller than the private banks would be interested in.

Full set

PS: the three little figurines on what looks like two legs
are ancient chinese coins.

holy carp, Rod, you ARE a walking encyclopedia..

You bear me undue expertise, SV.
I merely have access to an easily searchable database.
All the questions have been asked before on some forum or another
and I post what I have. :)

In reality,
I have trouble remembering where my slippers are.........