I have the Lowrance H20c and love it! I bought the Navionics 14xg mapping card for it. The coverage for that is....
"Entire Great Lakes, St Lawrence and the Canadian Maritimes, including Lake of the Woods, Rainy Lake, Lake Champlain, Trent Severn Waterway, Ottawa River, Rideau Waterway and the Finger Lakes."
BOQ is on that card.
When I ran the unit with no mapping card, it still plotted my position on the gps, so for what you are talking about, it should still fit the bill.