Dollar From My Coin Dealer ......

David,
Yes it's a 2 digit bookend and is also a trinary - 3 unique numbers in the SN. Do not get me wrong, but these have to be in AU / Unc condition as far as I am concerned. I collect UNC 3 digit bookends and save the 2 digit bookends that are similar to yours and they must be unique in some fashion and have eye appeal. I also take the note b4 and after as it relates to bookends. Example below of what I pulled from an unc stack yesterday.

5030 0350 - 2 digit (also saved 5030 0349 and 5030 0351)
5030 0503 - 3 digit (also saved 5030 0502 and 5030 0504)

BUT I did NOT take this into my collection - 5030 0550 - someone else may have.

As to your original ? on what to call it (Tri Pair bookend / Fancy 3 pair). People give all sorts of names to these and nothing is really defined. Someone posted this link below here a while back and is quite useful and gives a general idea of what to look for.

http://reviews.ebay.com/Fancy-Bank-...000001758931

Hope this helps.

Peace