These are directly related to the coins posted in Peter's thread "Troubled Coins", but since they're banknotes I thought I'd start a new thread. If a moderator wants to move it, please do.
Rubber stamped or hand marked banknotes...by pencil, pen, marker, etc... relating to the Irish Troubles era are extremely rare. Given the short life life span of paper currency and the concerted effort of the British and Irish governments to remove and destroy them, very few survived. Other than the five pieces posted, I've only seen two others. Both were marked in pencil, and since I didn't know the seller I didn't feel comfortable buying them. The counterstamped coins of the times were treated similarly, but because of the huge numbers put into circulation it was a monumental task that was doomed to failure.
In evaluating the legitimacy of these pieces I had to be very cautious, as it's much more difficult to separate fakes from the real thing. Coins not so much.
What it all comes down to is your source. Three of mine were acquired from a friend in Belfast, a man who grew up during the Troubles and taught me a lot about the military and political events of the time. Many years ago he sold me a small collection of counterstamped coins that his late father had collected from various sources. I had and still have implicit trust in him. These three notes were ones he acquired himself.
The unusual American Dollar bill was given to me several years ago by a long time coin dealer / friend who acquired it in a collection of coins and paper money he had bought. Although it may seem odd to see American money stamped with an Irish Nationalist slogan, it really isn't. There was strong support for the Nationalist cause in many US cities, particularly those with a large Irish American and Catholic communities. Boston and New York immediately come to mind.
The fifth note, the Irish Pound, I bought from a man in the UK who I had previously acquired coins from. He seemed an honest enough man who sold me legitimate coins, so I believe the note is as well. This is an unusual note as the slogan seems to be embossed or punch stamped on the paper in some manner. It appears that someone had traced some of it with a pencil to highlight it. My picture of this is too large a file, so I'll post it once it's resized.
The "Figt Back / Join the RA" banknote was deciphered by my Belfast source. Apparently, the stamper misspelled "fight" or simply abbreviated it. "RA" is a shortened form of IRA... I've seen this abbreviation on several coins before. Someone named Marty would likely be the issuer. "TL" stands for Turf Lodge, a heavily Nationalist area of Belfast, The 7(2?) may be the year it was stamped.