Yes, exactly - I also based my assumption on the very same Plymouth 2D.
Of course it could be any year after '54, but there are several same color pickup trucks in the back row, which could be new at the time...
Therefore I would not guess, say, 1959...
However, Ahem, I kind of asked for conversation over the Kaiser...
Here in North Europe Kaiser seems to be the most long gone of all dead marquees. Very few left, very few people know or appreciate them. On top of all they had assembly lines in Holland and Israel, resulting vague reputation. "not really an american car". The henry J's made in Haifa Israel were all crap - at least that's what my father & all other senior craftsmen been telling me.
On the other hand the fifties Kaiser Manhattans are really good looking cars. Also nice interiors - I wonder are they after all so bad?