Here are graphs of "significant wave height" [http://www.ndbc.noaa.gov/station_page.php?station=46217
courtesy of NOAA]
That means this is a graph of the average height of the 30% highest waves. [http://en.wikipedia.org/wiki/Significant_wave_height
wpedia explains more]
Peak wave heights are higher than the significant wave height. We weren't sailing the canoe right near these buoys, so our waves were different. So the answer to how big our waves were, is "pretty big, just like it seemed at the time". Does anyone have the wind and marine weather reports for the first weekend in October handy?