Ok, yes this is the lathe made for Sears by AA, I have the same one but sold under the Craftsman brand, Dunlap was an old Sears brand no longer used. It is kind of odd to see this one marked for Dunlap, because this is the restyled version that came out in the late 1940s and is usually badged as a Craftsman. Perhaps they continued the Dunlap name longer in Canada than the US.
It looks complete and in decent shape. These are extremely light duty and often have spindle damage from people trying to force them to do more than they were made for. They are popular and have something of a following. Not bad little lathes when used within their limits, would make a decent little lathe for model parts, pens and other small parts. A big downside is the lack of calibrated hand wheels so they are better suited to artistic (looks good by eyeball) projects rather than high precision parts.
Parts are available, but can be expensive. The only thing that jumps out at me is the change gears, do you have a full set or just what is on the lathe?