HB Supplies via Amazon offers the Whirlpool KitchenAid PUR Push Button Side-by-Side Refrigerator Water Filter 2-Pack, model no. 4396710P, for $46.11 with free shipping. That's the lowest total price we could find by $10. These filters are compatible with Whirlpool and KitchenAid side-by-side refrigerators with filter access in the base grill.
Note that this item is backordered until July 31, but can be ordered at this price for delivery when available.