Many thanks for wlin98004's help. wlin98004 is a member of CSS.
To translate this, you need to know a bit about American history. Benjamin Franklin is one of the founding father of the US. When we referring to Benjamins of something, it is mostly referring to as founder of something. This is not common used and very few people outside of US really understand it.
In the context of the Chinese postal system, I am not even sure we can call China as one of the first issuer of postage stamps. The first large dragon came out in 1878 which is 48 years later than the penny black. I read the entire paragraph, it took me a few reads before I understand the meaning of the paragraph. The writing is pretty poor in today's standard. In this case, you can't take literal translation of every word and phrase. You basically have to understand its meaning and re-write it in Chinese. My Chinese is pretty poor, so I will try my best. Here is my attempt.