Found this further information on the issue. Not at all sure how accurate or valid this data may be, but it does make for an interesting read on the subject:
Quote:
Labrador Essay
'We invite those who delight in stamps with stories back to them to pay attention to the three stamps of Labrador inscribed 'U.S.A. Post Office'
'W. R. Patton, editor of Canada and Newfoundland Section, Philatelic Gossip, 1927, supplies a few particulars of these stamps, but first let the author state that he purchased two sets from a Montreal dealer in September, 1926. These were in perfect condition, with no defacing marks whatever. The dealer knew little about them except that "many years ago an American had intended to use them on the Labrador Coast and the police had seized them, the lot being destroyed with the exception of a few sets, which had been eagerly sought after by collectors at the time".
'This is what Mr. Patton has to say: "There is a great stamp story behind these. I have been after it for nearly a year, but there is much to get yet. The Supt. P.O. Honolulu, got a great deal of information about these from a Private in the U.S. Army, stationed there, formerly of the Royal North West Mounted Police, who had seized them when bringing in an Eskimo prisoner from the far North, and later destroyed them in Toronto. An item in a philatelic paper published in Regina during 1910 referred to these stamps as having been seized in Montreal, however. It appears that the American gentleman who was responsible for the stamps had issued nearly One Million Dollars worth, as I have evidence that $675,000 were destroyed by the Government, probably more.
'The gentleman made a mistake in trying to annex this territory to the United States.
Source: Stamps of British North America, Fred Jarrett, pg. 138-139, Quarterman Publications, Massachusetts, 1975. Originally published, 1929.
Quote:
During 1908 British Colonial collectors were amazed to see stamps for Labrador inscribed "U.S.A. Postage". This was part of an elaborate scheme started in Montreal involving a special issue of three values from an American Company reputedly planning to develop this dependency.
Many of these stamps appeared on letters addressed to newspapers in Newfoundland, causing questions to be asked which resulted in the whole affair, company and all, being revealed as a work of fiction.
The American company claimed to have "received a charter from the governments of the USA and Newfoundland to develop the country, on condition that a postal service to various parts of Labrador was kept in operation during the navigable season.
Therefore the company had issued postage stamps of 5 cents, 25 cents, and 1 dollar; the latter value was intended for use only on parcels and registered matters, and would only be made use of by the officials of the Company.
No official confirmation was ever made, and the stamps were sold directly to the trade, until 1910, when the bulk of stamps were confiscated by Canadian authorities.
Lithographed by the Montreal Lithographing Co., perf. 12, 5 cents seal, 25 cents Inuit, $1 map in black, carmine & blue-green.
Posted 02/14/2011 11:43 am
). He goes into the future and they ask him where he's from. When he replies Canada, the Grandpa says "I think you mean North Montana, it hasn't been called Canada in years." 
