I have a list of US, WW, and US Possessions available for trade. I also have a want list of US, WW, and US Possessions I need for my collection. My duplicates are strongest in US Possessions (Hawaii, Canal Zone, US-Cuba, US-Puerto Rico, DWI, Guam, and US-Philippines). Happy to share my list or review you want list.
We ought to see what each of us is missing, still need a couple of the Philipine officials, some singles from Sc# 263-300 or so, and specifically 393, 446, 451, 462 in the regular issues. C32 and C35 seem to be impossible to find unused. Hawaii, looking for a 65 with relatively decent centering. (And a 61B if you have one laying around :-)