James Milton Sessions "Fishing Boats at Dock" watercolor

I found a copy at http://www.liveauctioneers.com/item/7526262. The price is pretty high so I'm assuming it's an original. The site doesn't say if it's a reprint or original.
On the paper on the back of my framed version it says "From Jean 1979", the paper hasn't been removed/replaced, so I assume it was at least framed at that time or earlier (or maybe someone just wanted it to look old...). It's in a less ornate frame than the one listed at the liveauctioneers website. It's covered in glass but I can see that the "paper" is rough, like canvas(?). We have not opened it to examine it. Did they make reprints/copies on canvas often in the 70s? Does anyone know what the value might be? I apologize for the quality and size of the picture, I had to use my phone. It looks exactly (as near as I can tell) to the one on the liveauctioneers website.