Canadian Coleman 500

A few weeks ago, I got my first Coleman 500 on eBay. It's a Canadian model, with a scalloped grill, and in great shape -- it fired right up. What appears to be a date stamp under the logo says "D 39". I figured this couldn't be true, since the Coleman Collectors Guide says the stove was only made from '42 to '49. (Coleman Collectors website says '42 to '53. This is also what I heard from Coleman USA, who added that the 500A (green painted fount) was made from '54 to '62). However, Coleman Canada says that indeed, the model was made in 1939, and that is the year the date stamp indicates for mine. They also said that their production records are not complete, so they don't know when the stove was first manufactured. Also, (tempting though it is to say D=April) they say that they don't know what the "D" indicates, and that "nobody knows". I apologize if this is "old news" to Celeman 500 experts out there, but I'm surprised and happy that the model has been around that long. I know Coleman Canada has had a certain amount of leeway in developing their own products since the 1920s, but I didn't know this was one of them.
....Arch