My canoe is canvas covered, dimensions are 15' long, 34" wide, 13 1/2" deep. All ribs are 1 1/2" x 5/16" and spaced at 1 1/2" apart. The decks are rounded and the gunwales are open. The serial number is 15-71621. I am the second owner & I have owned it for approx. 40 years and I restored it at that time. What model do I have if this is a Chestnut and how old is it? Any help will be appreciated.