Poster Stamp Paper For Poster Stamps

I found these poster stamps offered on ebay that I found rather curious, as they are promoting a company that supplied the poster stamp industry with the gummed paper needed to make them:



So with my curiosity getting the best of me, I wanted to date these poster stamps, so my research found this ad from 1912 (note the branch office on Nassau St., NYC, which was in the heart of stamp dealers of that day):



And this announcement of their merger in 1922:



So I've dated the poster stamps from within the decade 1912-1922. Can anyone pinpoint it any closer?

Could you please provide the link for these posters?


Cheers

wt1,

Great stamps and info.
I wonder if they sent some of their paper here:

Very cool!

Here it is. Asking price appears to be on the high side, though, and quite a lengthy time for the auction, probably both contributing factors to why there are no bidders yet.

http://www.ebay.com/itm/3-Poster-St...t_500wt_1127