Again, this is normal. Your original decks look standard for the time period during which your canoe was made. The decks you received from Old Town are the type they make for their canoes today (see attached). In fact, they're different from your in more that just the shape of the cutout- the shape as they taper from amidships to stem is also different- those on the earlier canoes are more delicate-looking; they are concave on the sides as opposed to being straight-sided. The asymmetry of the the cutout on the deck on the right is inexcusable (and are those cracks in the deck on the left?). They should be returned on that basis alone.
Question- the original deck you show looks pretty nice... why replace them?
Michael