I was not the first person to consider an ABNCo-only collection, and you won't be the last

Don't forget to include the, you know,
bank notes ABNCo printed along with the various types of stamps from the various countries.
https://en.wikipedia.org/wiki/ABCor...Corporation) ... ABNCo on de Wiki
You should
immediately treat yourself to a copy of
The Story Of American Bank Note Company, by William H Griffiths.
As re-published by Literary Licensing, LLC (2013) in Hardcover: ISBN 10: 1258759276 ISBN 13: 9781258759278
As re-published by Literary Licensing, LLC (2013) in Softcover: ISBN 10: 1258761270 ISBN 13: 9781258761271
As originally published? Get ready to pay real money for the 1959 edition.
https://www.newspapers.com/clip/222...ract_no_bid/ ... a fun read from the 18870531 issue of the Pittsburgh Daily Post ... ABNCo Wins Postal Note Contract ... which addresses issues of government efficiency, private contractors ...
the more things change the more they remain the samehttps://goscf.com/t/26504& ... an earlier SCF thread entitled
ABNCo and BEP EngraversSearch "ABNCo" on this site, and down the rabbit hole you'll go!
Cheers,
/s/ ikeyPikey