China Revenues - Help!

Hi - I'm mainly a collector of Asian paper money but recently branched out in to stamps as well. I'm becoming pretty familiar... but revenue and similar types of stamps are proving to be a nightmare to identify.

Any help with these would be appreciated:



From what I've tried to work out, the top green stamp may be from Taiwan. The middle red one seems to be a Peoples Republic overprint issue and the lower right stamp possibly a 1930s issue overprinted during the Japanese occupation?

Row 1 -- Republic of China, I remember seeing revenues from this series on documents of the 1950s, so yes it was likely issued after 1949, but the revenues I saw on document were not this exact stamp

R2S1 -- Republic of China, for Kiangsu (Jiangsu) Province
R2S2 -- People's Republic of China, surcharged for Shanghai
R2S3 -- overprinted for Hopei (Hebei) and Beiping (Beijing), don't know if it was an occupation issue

Thank you for the info khj; very useful.

I'm surprised I didn't notice the Shanghai name in the PRC surcharge stamp!