Lot
464 
Canada, 1959, 5¢ St. Lawrence Seaway, center inverted, tied on small piece by wavy line machine cancel, exceptional centering and margins, rich bright colors, Extremely Fine, an especially choice used example; with 1969 B.P.A. certificate. Scott No. 387a $7,500.
ONE OF THE FEW USED OFF-COVER EXAMPLES OF THE 1959 5¢ ST. LAWRENCE SEAWAY WITH CENTER INVERTED.
There are about 200 mint Seaway Inverts in private hands. Quite a few of the Seaway Inverts were actually used by the public before they realized what they had. With only 16 examples recorded on cover, it would seem even a used example would be far rarer than mint however catalog values seem to indicate to the contrary.