Yes it is difficult to positively id this mower when you don't know if the parts are original ,like fuel tank ,wheels,handle bars,engine ,etc.
The 1987 newspaper ad was the only 1987 ad I could find with the large Victa decal on the front of the base instead of the small Victa badge.
I found a 1985 Commando Victa mower rusting away out back and thought it looked very similar except for the top plastics on motor and my model number on the air cleaner says it's a 1984 model but the engine number shows 1985.