I would be all over that, really nice original looking 5-window. Interestingly has a Chevrolet 235 in it so must be a bit of history to it. I know here in non-running condition a truck like that is 5-6k. If you can get a deal on that truck you have a keeper in my opinion.
Up here it's probably worth about that in running condition.
Interestingly enough in some years the Canadian-built GMC trucks had Chevrolet engines, so I wonder if it's a Canadian GMC? I don't know if the model number is a tip-off?
It does look like a good start.